Florida now more populous than New York

Earlier this week the US Census Bureau released the 2014 population estimates.

A few highlights:

Florida passed New York in population size.

North Carolina also passed Michigan, and North Dakota passed Alaska.

California still largest state in the US, but #2 Texas is adding 40,000-80,000 more people per year than California is. (Still, at that rate it will take nearly 150 years for Texas to overtake California).

Population pyramids (interactive)

They're not quite ready for prime-time yet, but I've been working on interactive population pyramids that allow a user to compare across regions and points in time.

Stay tuned for their official launch later this year as part of PRB's World Population Data Sheet.

Population Profile: Alabama

POPULATION GROWTH IN ALABAMA:

Population in 2010: 4,779,735
Population in 2000: 4,447,100
Growth rate 2000 to 2010: 7.5%
Sources: U.S. Census Bureau, Census 2010 and Census 2000

Place of Birth: Percent of resident population born in the state of Alabama:

Source: U.S. Census Bureau, American Community Survey 2007-2011

AGE STRUCTURE:

Median age in 2010: 37.9

Alabama Age Structure in 2010:

Source: U.S. Census Bureau, Census 2010 and author's calculations

PUBLIC HEALTH:

Birth rate: 12.4 per 1,000 population (compared with national rate 12.7)
Fertility rate: 61.8 per 1,000 women age 15-44 (compared with national rate 63.2)
Infant mortality rate: 8.28 per 1,000 live births (compared with national rate 6.39)
Sources: U.S. Centers for Disease Control and Prevention: preliminary birth data for 2011, final death data for 2009

Life expectancy: 75.2 years (compared with national 78.6)
Source: Kaiser Family Foundation state health facts 2007

Adult obesity rate in 2011: 32.0 percent
Source: U.S. Centers for Disease Control and Prevention, Behavioral Risk Factor Surveillance System

OTHER FACTS:

Only 3.4 percent of the population in Alabama is foreign-born, compared with a national average of 12.8 percent.
Source: U.S. Census Bureau, American Community Survey 2007-2011

Despite the holiday's association with New Orleans, it is Mobile, Alabama that gets credit for hosting the first Mardi Gras celebration in North America in 1703.
Sources: CNN and History Museum of Mobile

Nation's largest metros growing, but reasons vary

America's biggest metropolitan areas are growing, but for very different reasons, according to a new report from the U.S. Census Bureau.

Among metropolitan areas of 2.5 million people or larger, only Detroit lost population between July 1, 2010 and July 1, 2011. The other twenty large metro areas all saw population growth. However, drivers of growth varied widely among metropolitan areas.

Source: U.S. Census Bureau

DRIVERS OF GROWTH:

Population change occurs because of births, deaths, and migration. Births and deaths, collectively, are referred to as "natural increase."

At the state, county, and local level, migration can measured in a variety of ways, but is often estimated in terms of net international migration (those moving into, or out of, an area from abroad) and net domestic migration (those moving into, or out of, an area from another area within the same nation).

NET DOMESTIC OUT MIGRATION IN THREE LARGEST METROS:

In the nation's three largest metropolitan areas, New York, Los Angeles, and Chicago, population grew as a result of births, longer life expectancy, and international migration.

However, net domestic migration estimates show that more residents moved out of these areas to other parts of the United States than moved into these areas between 2010 and 2011.

DON'T MESS WITH TEXAS:

The largest metropolitan areas in Texas, however, showed an entirely different pattern, acting as magnets for migration from other parts of the United States.

The Dallas-Fort Worth and Houston metro areas both grew by more than 100,000 during the year with 20 percent or more of that growth coming from net domestic migration.

SUNSHINE STATE:

Miami and Tampa, Florida's largest metropolitan areas, were also net-attractors of residents from other parts of the U.S. Miami showed fairly even population growth across all categories (20,400 natural increase, 35,200 international migrants, 36,200 domestic migrants) for net population growth of more than 92,000.

While Tampa attracted more than 27,000 domestic migrants, net international migration was less than 7,000, and an aging population resulted in net natural increase of only 2,300, the lowest of all 21 large metropolitan areas in the report.

GOLDEN STATE:

As noted above, more residents moved out of the Los Angeles metro area than moved in between 2010 and 2011. However, other large metros in California fared better. As a result of net domestic in-migration San Francisco gained 5,900, Riverside-San Bernardino gained more than 15,000, and San Diego grew by 800.


Methodology and Source Notes:
The figures shown above are from the U.S. Census Bureau Population Estimates (vintage 2011). Additional information on patterns of migration can be found in the Current Population Survey report on geographic mobility.

Data link roundup (week of November 30, 2012)

The week's top data analysis links...

ANALYSIS ADVENT

The Economist magazine posted its data analysis Advent calendar. Each day a new "most popular chart of the year" will be revealed.


PROLIFIC POTATO

It has long been suspected that the cultivation of potatoes played a starring role in the demographic transition by increasing nutrition and extending life expectancy. New estimates suggest that a quarter of "Old World" population growth from 1700 to 1900 can be attributed to the tuber.

Source: Library of Congress

TO SECEDE OR NOT TO SECEDE? (Actually, that's not the question...)

Despite widespread media hype about the post-election secession movement, and reports of nearly a million signatures collected across 60 petitions filed on the White House website, careful analysis of the data show that many of the signatures were the result of single individuals signing multiple petitions.

Once duplicates were removed, only 0.1% remained (about 300,000 signatures in a nation of more than 310 million people), according to results published by Neal Caren at UNC Chapel Hill.


BEST CHART OF THE WEEK

Things on a university website:

Source: xkcd

Geography Awareness Week: Waterfront Property

This week we'll be celebrating Geography Awareness Week by highlighting unique spatial visualizations of data.

Image source and source notes: Counties are based on 2010 geography and historical populations are based on population estimates derived from decennial census data (1790-2010).
Point locations are based on population-weighted county centroids.

According to NOAA, today more than half of the U.S. population lives in a coastal county. Recent graphics from the U.S. Census Bureau put the proportion closer to one third.

Why are the two measures so different?

The answer is in how you define "coast."

The Census Bureau analysis, pictured above, defines a "coastal county" as any county in which a portion of the county's boundary is adjacent to an ocean. NOAA's analysis includes the Great Lakes in the definition of coastal. Densely populated areas, like Chicago, account for the difference in the two measurements.

Geography Awareness Week: Charting population density along America's highways

This week we'll be celebrating Geography Awareness Week by highlighting unique spatial visualizations of data.

The U.S. Census Bureau produced a series of graphics that show population density along some of the nation's most and least heavily populated transportation corridors.

Image source and source notes: Population density is based on average population density within 5 miles of the highway, in 2-mile increments, using 2010 block group centroids and 2010 Census population counts.

According to the Census Bureau:

Running from Los Angeles to Jacksonville, I-10 passes through 8 states and several major cities and traverses the 3rd largest population among the country's interstate highways. Population density within 5 miles of the interstate show several lengths with very low population density, including stretches between El Paso and San Antonio. Selected cities along the route are labeled, for reference, with cities of 250,000 or more shown in bold and with filled circles.

For comparative purposes, the Census Bureau provides a similar population density chart for the I-90 corridor, which runs along the northern part of the United States from Seattle to Boston. The highway, despite connecting Seattle, Chicago, and Boston, passes through some of the least densely populated areas in the nation.

The Great Migration

The U.S. Census Bureau analyzed data on population change, by race, for two key periods that characterize The Great Migration (1910-1970) during which blacks residents moved out of the southeast.

The color of map bubbles represents the percentage point change in black population in a given city between 1910-1940 (left) and 1940-1970 (right). Darker orange shows that the black population increased as a share of the city's population. Darker blue shows that the share decreased.

Image source

What I find interesting about the 1940-1970 chart is that New Orleans and Atlanta (and, to a lesser extent, Augusta and Chattanooga) both buck the otherwise nearly universal southern trend. Each city saw an increasing proportion of black residents 1940-1970.

However, it is important to note two key caveats in the data:

• Population shares may have changed due to migration or as a result of natural increase (births, life expectancy), though most of the change is attributable to migration.
• Data are shown only for cities "that were either in the top 100 cities in the country or top 3 of a state and had a Black population of at least 100 people." This means that some change shown on the chart may have been a shift from suburbs-to-cities or vice-versa.

World population = 7 billion

It just so happens that this year the United Nation's announcement that the world's population reached 7 billion coincides with the lesson I teach on demographics, population growth, and urbanization in Intro to Sociology.

In searching for materials to make this data-intensive lesson more accessible to intro students, I came across this video from National Geographic.


It provides a series of facts about global population growth in a format that is eye-catching and memorable. This video is perfect for introducing the concept of demographic change.

Aging population and driving

This story in today's San Diego Union Tribune, about a fatal accident involving a 71-year-old driver, prompted me to post a piece I've been working on for a couple of weeks...

Six months ago the first wave of Baby Boomers turned 65, prompting questions about how the nation's transportation system will adapt to an aging population. There are some benefits that may arise from having an older population, and there will undoubtedly be challenges.

As the population ages we may care less about our cars. A Gallup poll in 1991 found that 20 percent of Americans found driving to be a chore. The same response in 2006 got a 40 percent boost to 28 percent. When you drill down into the details of the survey, likelihood of taking a ride “just because it’s fun” decreases substantially with age. In short, an older population is less likely to enjoy driving.

And, contrary to most road-rage induced stereotypes, older Americans also drive more safely. (However, there are some limitations to that trend, as described below.)

In their 2009 study of aggressive driving behavior, AAA found that at age 16 nearly 60 percent of drivers show aggressive behavior. By age 35 aggressive driving falls to 35 percent and by age 60 is below 27 percent.

With an already aging population, safer driving is beginning to show up in accident statistics. According to the U.S. Department of Transportation:

“in 2010 the number of traffic fatalities in America fell to the lowest levels since 1949...despite a sharp increase in the number of miles Americans drove last year - 21 billion additional miles. In addition, the rate of road fatalities in the U.S. has also dropped to its lowest level since 1949. Over the last five years, traffic deaths have declined by 25 percent…And the rate of fatalities per million miles traveled fell to 1.09 from 1.13 in 2009.”

Transportation Secretary Ray LaHood credits this to “the combined efforts of DOT, states, law enforcement, safety organizations, and America's drivers who are taking personal responsibility for their driving habits.” But I also see a demographic shift at play, much as there was a demographic influence on falling crime rates, beginning in the mid-1990s.

However, as opening article implies, there are also substantial health issues that may impair the driving of older Americans.

For example, the likelihood of reporting some form of disability DOUBLES between the age groups 65-74 and 75 and older (from 25 percent at age 65 to fully half the population age 75+). Similarly, according to data from the U.S. Centers for Disease Control and Prevention 10 percent of older men and 15 percent of older women reported cutting back on driving due to a physical problem in the past year. And, for a combination of reasons, older drivers are likely to avoid driving in certain conditions. Older drivers tend to avoid driving at night, driving in bad weather, and (to a lesser extent) driving in heavy traffic.

All of this adds up to some very complicated issues facing the nation's transportation system. Fortunately, research is underway to better understand the implications of age-related health issues on transportation at institutes such as the Age Lab at MIT.

Hurricane seasons begins

It's June 1, so the 2011 hurricane season has begun...

Nearly 37 million people live in areas most at risk of hurricanes, an area covering 179,000 square miles along the coastal region stretching from Texas to North Carolina, according to the U.S. Census Bureau. Hurricanes occasionally strike farther north, but such events are rare.

Hurricane History
The Department of Housing and Urban Development estimates that in the summer of 2005 hurricanes Katrina, Rita, and Wilma damaged "more than one million housing units across five states." Of the damaged homes 515,000 were in Louisiana, 220,000 in Mississippi, and nearly 140,000 in Texas.

By 2010, according to the HUD study, three quarters of the 2005 hurricane-damaged properties on "significantly affected" blocks were in good condition (at least on the outside*), but nearly 15 percent of the properties still had substantial visible repair needs, and 11 percent no longer contained a permanent residential structure. Louisiana homes, of the state affected, are most likely to still have unrepaired damage. Mississippi homes were most likely to be either repaired or entirely demolished and left vacant.
*We should note that these estimates do not include homes with mold or other water damage issues that might render the structures uninhabitable.

From a business perspective, in the year following Katrina New Orleans had about 95,000 fewer jobs, with most losses in tourism and port operations. It took nearly two years after Katrina for the number of restaurants in New Orleans to rebound to it's pre-hurricane level (according to restaurant critic Tom Fitzmorris in his book Hungry Town).

Hurricane Demographics
In addition to their physical and economic damage, major hurricanes can cause huge demographic shifts. For example, during hurricane Katrina approximately 1.5 million people over the age of 16 left their homes in Louisiana, Mississippi, and Alabama. And while many have returned, not all have. For example between 2005 and 2010 New Orleans saw its population decline by 25 percent from an estimated 455,000 before the hurricane to 344,829 as of April 1, 2010.

And while New Orleans tends to dominate the news headlines because of the broken levees, Pass Christian, MS actually has sustained a greater proportionate loss in population. Though a small town before Katrina (just under 7,000 according to 2005 Census Bureau estimates) the population had shrunk in half in the year following the hurricane, and many residents did not return. The 2010 Census count shows a resident population of only 4,613 - a sustained decline of 34 percent since the hurricane. Gulfport, MS also declined by an estimated 5,500 residents (-8 percent) between 2005 and 2010.

Less notorious, but just as significant in terms of population shift, was Hurricane Ike in Galveston, TX. Nearly 10,000 residents remained displaced two years after the hurricane. The estimated population before Ike was 57,000 but was only 47,743 at the 2010 Census. The HUD report on housing shows that one quarter of homes in Texas hurricane-affected neighborhoods still showed significant damage in 2010, in part because of the 2005 series of hurricanes and in part because of Ike.

In natural disasters traditional sources of demographic data (building permits, school enrollment records, utility hookups, drivers licenses, etc...) are either no longer available, or provide misleading information about the displaced, remaining, and returning population. Some of the most clever demographic techniques I have seen to date were hurricane-related. At the 2010 Applied Demography conference Mark VanLandingham and Janna Knight presented their techniques for reverse-estimating the post-Katrina population of New Orleans. And Nazrul Hoque, Alelhie Valencia, and Karl Eschbach presented their techniques for filling in the data gaps for post-hurricane Galveston.

Hurricane Preparedness
And in case all this talk of hurricanes has you thinking it's time to update your emergency preparedness kit, the CDC has developed a useful but tongue-in-cheek checklist that will get you through any disaster - even a zombie apocalypse!
Click on image for more information from the CDC.

Image of Hurricane Katrina in the Gulf of Mexico courtesy of NASA-GSFC, data from NOAA GOES

Whadja say? I can't heer yooooo.

Thanks to The Economist for pointing me to this fascinating map from Rick Aschmann.

Having lived in each corner of the country, and traveled to more than half of the states, I find accents fascinating, but never considered mapping the data. I just knew, growing up in southern New England, that "systematic r-dropping" led the word "cart" to sound like "cot" (or, more unfortunately "party" to sound like "potty.") I did not know, as Aschmann documents, that this accent type does not exist anywhere else in the world! Aschmann's work provides an interesting visual display of regional dialects, and also provides a wealth of qualitative data, including samples, on many of them.

Despite the incredible wealth of data on accents and dialects, I do think data for non-English-speaking areas are lacking. For example, the map includes Navajo, despite the fact that fewer than 400,000 people (0.13% of the nation's population) speak Navajo or another Native American language. However, the only areas labeled "Spanish Speaking" are in Mexico. Yet more than 12 percent of the U.S. population speaks Spanish. Spanish-speaking populations account for an even higher share in states along the border. Nearly 30 percent of the population age 5 and older speak Spanish as a primary language in California and Texas. Similarly, in California nearly 3 percent of the population speaks Chinese, another 2 percent speak Tagalog, and 1 percent each speak Vietnamese and Korean. (Source: U.S. Census Bureau, 2009 American Community Survey).

Click on the map, or follow the link below, to access the original.
Original map: http://aschmann.net/AmEng/#DialectDescriptionChart

Go West, Americans! (Or maybe South?)

Since the Census Bureau started keeping score in 1790, the nation's population has grown fastest in the western and southern regions, shifting the nation's "mean center of population" in a steady march across the continent.

According to the Census Bureau:

The center is determined as the place where an imaginary, flat, weightless and rigid map of the United States would balance perfectly if all residents were of identical weight.

Tracking the mean center of population tells a story of the nation's growth, conflicts, and social change. This interactive map from the U.S. Census Bureau shows the shifting mean center of population over time:


Today's mean center is in Texas County, Missouri - more than 1,000 miles from the first recorded center in Kent County, Maryland (1790). Some of the biggest shifts over time show the nation's development, and at times, growing pains.

Major shifts over time:
1790: First mean center is calculated as falling about 23 miles east of Baltimore, MD.

1810: The Louisiana Purchase (1803) doubled the land area of the nation, and the mean center shifted into Virginia.

1860: The center shifted by more than 80 miles (biggest shift on record) thanks to rapid growth in the nation's western states, driven in large part by the Gold Rush.

1870: Just ten years later the mean center of population experienced it's biggest shift to the north, as Northeastern and Midwestern cities experienced rapid post-Civil War growth as people fled the war-ravaged South. Also during this time Alaska became a U.S. territory (1867).

1920: The smallest shift on record was between 1910 and 1920. The nation's current territory had already been acquired, slowing the rate of westward expansion. The Northeast and Midwest saw large inflows of international migrants. And last, but certainly not least, there was substantial migration of black/African American population out of the South and into the Northeast and Midwest, precipitated by the intense racism that spawned the Jim Crow laws.

1950: After six decades in Indiana (the longest in any one state), the center finally crossed state lines into Illinois.

2010: The center has its biggest recorded shift to the south, as Georgia, Florida, North Carolina, South Carolina, and Texas record rapid population growth.

Recession is bad for the baby business

For another sign that The Great Recession is taking a toll on the population, look no further than the local maternity ward. The birth rate is falling after many years of slow but steady increase. Research that I presented at the 2010 Applied Demography conference tracked the trend in fertility during recessions, controlling for factors such as female labor force participation, contraceptive technologies, and other social trends. Recent publications from the Pew Research Center arrived at the same conclusion: births fall during recessions.

This trend may be contrary to popular logic. It is common to assume that for two-income families, a layoff means that one member of the family has more time on his (or her) hands for child-rearing and for... to be delicate... the activities that lead to child-rearing. However, research suggests that economically depressed times drag down more than just the stock market.

According to a survey conducted by the Guttmacher Institute, "Sixty-four percent of women agree with the statement, 'With the economy the way it is, I can’t afford to have a baby right now'."

Overall the survey suggests that women want to delay having a child because of financial instability resulting from the recession, and that most (but not all) are being more careful about contraception as a result. Data from the Nielsen market research company confirms that condom sales have increased since the recession started.

The survey responses mirror a trend that is beginning to show up in birth certificates. Nationwide the birth rate fell by 4 percent (from 4.3 million to 4.1 million) between 2007 and 2009. To put that into perspective, 185,000 fewer births is equivalent to the population of Little Rock, AR. Data for the first half of 2010 shows a continuing decline (data from CDC).

Declines were sharpest in the southeast and western states - those hit earliest, and perhaps hardest by the recession (see map). For example, the number of babies born to residents of California fell by nearly 24,800 (4.5%) between 2008 and 2009, and by more than 40,000 (7%) between 2007 and 2009, according to records from the California Department of Health.

The falling number of births can be linked to declining fertility across almost all population groups. This means that across all race and ethnic groups, and across almost all age groups, women are having fewer babies in 2009 than in 2007. Only women over age 40 saw any increase in birth rate over the past two years, and those minor increases were not sufficient to offset declines in all other groups.

So for as long as the economy remains in the doldrums, savvy market watchers should be investing in condoms, not in baby gifts.

Census Data - as it is released

From the U.S. Census Bureau...
Click on a state to see county-level data detail.

Fascinating tool for visualizing demographic change over time

I had to share this fascinating visualization tool from NPR on the changing demographics of the United States (and each state) over the past 100 years.

Just keep in mind that the means of collecting race/ethnic data, and even the definitions of race have changed dramatically over the decades. For example, Census questions about Hispanic origin have not been asked consistently over time. Today's Census forms are self-reported, but prior census counts relied on a person's surname to determine Hispanic origin (so if your last name "sounded Hispanic" to a Census worker, you would be classified as such, whether your ancestors were Latino or not).

To link to the tool on NPR's website:
http://www.npr.org/2011/02/15/133692251/americas-shifting-populations

Happy graphing!

The hefty toll of the obesity epidemic

Obesity rates are going up, up, up.

Today, Colorado has the nation’s lowest rate of adult obesity, at 18.6 percent, followed by Washington DC at 19.7 percent. California ranks 17, tied with Alaska, with an estimated 24.8 percent of adults in the obese category. The nation’s highest rates of obesity are in the southeast, with Louisiana (33%) and Mississippi (34%) topping the charts, according to data released last week by the Centers for Disease Control and Prevention (CDC).

Compare this with data from 1990, and the picture becomes quite alarming. In 1990 ten states had obesity rates below 10 percent. Today none do. In 1990 no states had obesity rates above 15 percent. Today none have rates below 15 percent.

According to the CDC, obesity is “defined as a Body Mass Index (BMI) of 30 or greater.BMI is calculated from a person's weight and height and provides a reasonable indicator of body fatness and weight categories that may lead to health problems. Obesity is a major risk factor for cardiovascular disease, certain types of cancer, and type 2 diabetes.”

These obesity-related diseases carry a hefty price tag. Estimates in 2000 put obesity-related health care costs in California at $7.7 billion dollars, and the national cost at $75 billion. According to more recent projections from United Health Foundation, the American Public Health Association and Partnership for Prevention, if current trends continue costs may reach as high $318 billion in the next eight years. Even if rates stay steady at their current high levels the report finds that “the U.S. could save an estimated $820 per adult in health care costs by 2018 ? a savings of almost $200 billion dollars.”

Perhaps not surprisingly, obesity is strongly correlated with physical activity. States where a high proportion of commuters walk, run, or bike to work have some of the nation’s lowest obesity rates. For example, nationwide about 3.4 percent of commuters walk or bike as their primary mode of commute to work. In Colorado, with the nation’s lowest obesity rate, the walk-or-bike rate is 4.2 percent - 25 percent higher than the national average. In Washington DC with the nation’s second lowest obesity rate, the walk-or-bike rate is 13.7 percent. Conversely, commuters in the three states with the highest levels of obesity (Mississippi, Louisiana, Tennessee) are only about half as likely to walk or bike to work as the national average.

For original publication, please see: http://www.examiner.com/x-43439-San-Diego-Economy-Examiner~y2010m8d10-The-hefty-toll-of-the-obesity-epidemic

Recession ages the labor force

The sour economy may have discouraged many job seekers into giving up the job hunt for now, but that is not the case for those age 55 and older. While labor force participation rates have fallen across most age groups, rates have actually increased for those age 55 and older. In fact, even with higher unemployment rates, the total number of U.S. workers age 55 and older has actually increased in the past two years, while those age 16-19 have suffered the greatest employment losses.

It is worth noting, however, that working at older ages is not an entirely new trend in the United States. In the 1960s and early 1970s the majority of men age 55 and older were in the workforce. That proportion did not dip below 50 percent until 1975, reached its bottom in 1993, and has been increasing since that time. According to data released by the U.S. Bureau of Labor Statistics labor force participation in 1993 was 29 percent for men and women age 55 and older. That figure has risen to more than 40 percent today.

This trend toward longer work-life is driven by longer life expectancy, less secure retirement, and also by job satisfaction. Surveys of the population in Japan, with some of the world's highest rates of labor force participation in older populations, report that half of workers age 60 to 69 reported staying in the workforce because "working is conducive to improved health." This may be more true in today's knowledge-based economy than ever before, as working provides social connections that may fade in retirement.

Nevertheless, older workers tend to earn less than their younger counterparts. For example, workers age 65 and older make, on average, $90 less per week than those in other age groups.

With the aging of the Baby Boom population leading to rapid growth in the oldest age groups, coupled with higher rates of labor force participation, the United States can expect considerable competition in the job market for the foreseeable future. On the positive side, a higher rate of labor force participation means that companies may have an easier time retaining a workforce with many years of experience. Older workers, on the other hand, will need to keep skills sharp in order to overcome the wage gap.

Demographic Trends in San Diego: What Planners Can Expect in 2010

... article originally appeared in The Planning Journal, Spring 2010

Population Growth 1910-2010
In the past 100 years, the San Diego Region (18 cities and unincorporated county) has grown from a small city of 60,000 people to a thriving metropolitan area of 3 million. In San Diego’s early years, Census figures show that the county’s population nearly doubled every ten years from 1910 to 1960. Between 1960 and 1990 growth slowed to an average increase of approximately 33 percent every ten years. Growth slowed again in the 1990s, with increases averaging less than 15 percent in each of the past two decades.

Migration Patterns
Migration was the primary driver of population growth in San Diego’s early years. Historically, most growth in Southern California was a result of in-migration from other parts of the United States and from other countries around the world. However, according to a recent study released by the University of Southern California Population Dynamics Research Group, that trend has shifted statewide, with most of the population now being, in the words of the study authors, “homegrown” (i.e. born in California). San Diego, however, lags behind the state in this trend, with 52 percent of residents having been born outside of California, according to 2008 data from the American Community Survey.

The 2010 Census short-form does not include a question about place of birth or place of residence five years ago, as prior long-form survey questionnaires did. However, information on 2010 population characteristics provides concrete data against which migration trends can be measured. For example, knowing the 2000 Census population characteristics of a region, and the survival rate and fertility rate of the population, demographers can determine what the population in 2010 could look like in the absence of any migration. Comparing that 2010 hypothetical projection against actual 2010 Census data provides useful insights into which groups moved into or out of a community during the decade. Thus, the 2010 Census population data will provide a key benchmark for measuring migration trends.

With respect to local planning, the key point to note in migration trends is that "the future is us." The people we are planning for are ourselves, our neighbors, and our children. The years of double-digit population growth due to large in-flows of migrants appear to be over, at least for now.

Age StructureThe median age in San Diego increased from 31 years in 1990 to 33 years in 2000 and is estimated to be 35 years in 2009. 2010 Census data will likely show a median age in the mid-30s. While this may not sound like much of a change, the underlying age structure changes are dramatic. Between 1990 and 2000 the county's young population (residents under age 18) grew by 112,700, compared with population growth of only 40,600 in the population age 65 and older. This means that there were nearly three additional children in the county for every additional senior during the 1990s. In the ten years since the 2000 Census all indicators point to a reversal of that trend, with slightly more growth in the senior population than in the population under age 18.

The population is growing across all age groups, but this trend toward an aging population is here to stay. An aging population will result in changing needs and preferences for the local population. For example, older residents may have different residential structure type preferences than college students or families with children. With respect to transportation planning, traffic patterns may change as a result of more off-peak travel by retired residents. These are just a few specific examples of a much broader issue. Planners should be aware of their community's aging population needs as they update public facilities plans, transportation plans, zoning ordinances, and other plans.

2010 and Beyond
The demographic characteristics of the San Diego Region will continue to evolve over time. San Diego is transitioning from a history of high-volume in-migration, to a more “homegrown” population. The future we plan for is our own. Each generation of residents living here today enjoys longer life expectancy Longer life expectancy means that much of the region’s future population growth will be in the oldest age groups. The 2010 Census will provide a clear snapshot of the region’s changing demographic characteristics and will provide planners with plenty of food for thought for the decade ahead.