State and County Population Projections

State and County Population Projections

ASDC Annual Meeting

Carolyn Trent, Socioeconomic AnalystAlabama State Data Center

Center for Business and Economic Research

November 2, 2012

Culverhouse College of Commerce and Business AdministrationThe University of Alabama

Population Projections

Based on population change between the 2000 and 2010 Censuses and recent birth and death data. Assumptions are made about future trends in fertility and mortality.

Utilize a cohort component model of the form: Pop(new) = pop(old) + births – deaths

+ in-migration – out-migration

Calculated for the state and counties for 5-year age groups from 0-4 to 80-84 and 85+, for males/females, races white/black and other. Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 2

Inputs to the ProjectionsFor the state and each county, the following are compiled:

Population by age/race/sex for 2000 and 2010.

Total number of births by race of mother and sex of child for 2000 through 2010 (from Alabama Center for Health Statistics).

Total number of deaths by race, sex, and age group for 2000 through 2010 (from ACHS).

Census 2000 and 2010 group quarters populations.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 3

Census data inputsWe use bridged-race population estimates from NCHS instead of raw Census data.

These data are calculated by the Census Bureau for NCHS annually to create race categories that are more compatible with race information collected on state vital records.

Collapses the 31 race categories collected in the Census into 4 categories: White, Black or African American, American Indian or Alaska Native, and Asian or Pacific Islander.

The NCHS groupings reallocate the multiple race and some other race Census categories. Hispanics often identify themselves as some other race.

Census 2010 data have Alabama with 3,275,394 white and 1,504,342 black and other residents. The bridged 2010 data give 3,399,975 white and 1,379,761 black and other residents.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 4

Fertility RatesUsing annual birth data by race of mother and sex of child for 2000 to 2010, we calculate the following for the state and each county:

General fertility rate by race for women aged 15 to 44 in 2010, using average births from 2006 to 2010.

Birth rate adjustment factors by race for each 5-year period, based on factors calculated by the Census Bureau for their most recent national projections.

Share of births by race that are male versus female, based on all births from 4/1/2000 to 4/1/2010.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 5

Mortality RatesWe begin with annual death data by 5-year age groups, race, and sex for 2008 to 2010 for the state and each county and calculate:

A one-year mortality rate for each age/race/sex category by averaging the three years of deaths and dividing by the 2010 population. These are converted to multi-year rates.

Mortality adjustment factors for each 5-year period, using actuarial tables from the Social Security Administration.

We substitute in state rates for cells with fewer than 5 deaths on average.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 6

Special PopulationsPopulations of people in prisons, colleges or universities, or other large institutions are not influenced by the usual demographic factors. For 18 Alabama counties where at least 2.4 percent of the total population lived in group quarters, special populations were estimated for 2000 and 2010 by age, race, and sex. These populations were held constant across the projection period.Fertility rates were adjusted in counties with large university populations.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 7

Producing ProjectionsThe cohort-component program is run separately for each geography, generating projections for 5-year intervals from 2015 to 2040.

The cohort aspect of the projection process is that the population in each 5-year age group is aged over the 10-year intercensal period—i.e., individuals who were 20-24 in 2000 will be 30-34 in 2010.

The unknown part of the projection is migration rates, which are derived as the residual of the change from 2000 to 2010 after adding births to the 2000 base population and subtracting deaths.

Migration rates are dampened for each 5-year projection period under the assumption that the rate of people leaving a county will slow over time as will the rate of individuals moving in.

In this new series of projections, county results are summed across all age/race/sex groups to derive the state totals.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 8

What demographic factors will be at play

over the next 30 years?

How will Alabama’s population be changing?

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 9

Baby boomers will be turning 65 from 2011 through 2029; retirements will open up

jobs for Generation Y

Source: U.S. Census Bureau.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 10

Our population is aging due to demographic factors and

longevity increases

  Alabama Population by Age Group  2010 and Projected 2025 and 2040             

  2010 2025 2040 Age Group Number Percent Number Percent Number Percent

 0-4 years 304,957 6.4 307,591 5.9 324,612 5.8

 5-19 years 971,355 20.3 998,297 19.0 1,004,970 18.1

 20-64 years 2,845,632 59.5 2,925,619 55.8 3,037,589 54.6

 65+ years 657,792 13.8 1,010,916 19.3 1,199,853 21.6

 85+ years 75,684 1.6 94,122 1.8 165,041 3.0

 Total 4,779,736 100.0 5,242,423 100.0 5,567,024 100.0

Source:  U.S. Census Bureau and Center for Business and Economic Research, The University of Alabama.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 11

Alabama’s median age rose from 35.8 in 2000 to 37.9 in 2010

10.0 8.0 6.0 4.0 2.0 0.0 2.0 4.0 6.0 8.0 10.0

0-4

5-9

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

0-4

5-9

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

Alabama Total Population 2000 and 201020002010

Percent by Age Group

Age

Gro

ups

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 12

Baby Boomers move from ages 46-64 in 2010 to ages 61-79 in 2025

10.0 8.0 6.0 4.0 2.0 0.0 2.0 4.0 6.0 8.0 10.0

0-4

5-9

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

0-4

5-9

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

Alabama Total Population 2010 and 202520102025

Percent by Age Group

Age

Gro

ups

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 13

In 2040 Gen X will be 58-75 and ages for the larger Gen Y will hit 39-57

10.0 8.0 6.0 4.0 2.0 0.0 2.0 4.0 6.0 8.0 10.0

0-4

5-9

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

0-4

5-9

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

Alabama Total Population 2025 and 204020252040

Percent by Age Group

Age

Gro

ups

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 14

A relatively older white population is contributing to slower growth

going forward  Alabama Population by Race  2000 to 2010 and Projected 2025 and 2040               Total White Black and Other

Year NumberPercent Change Number

Percent Change Number

Percent Change

 2000 4,447,100  3,218,218   1,228,882  

 2010 4,779,736 7.5 3,399,975 5.6 1,379,761 12.3

 2015 4,943,866 3.4 3,487,124 2.6 1,456,742 5.6

 2020 5,101,172 3.2 3,568,000 2.3 1,533,172 5.2

 2025 5,242,423 2.8 3,637,059 1.9 1,605,364 4.7

 2030 5,365,245 2.3 3,694,126 1.6 1,671,119 4.1

 2035 5,471,880 2.0 3,742,196 1.3 1,729,684 3.5

 2040 5,567,024 1.7 3,785,415 1.2 1,781,609 3.0

Source:  U.S. Census Bureau and Center for Business and Economic Research, The University of Alabama.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 15

Some counties will thrive over the next 30 years, while others will

dwindleEconomic development successes, local entrepreneurship, quality of life enhance-ments, retiree attraction, and workforce skills training could improve these trends

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 16

31 Alabama counties lost population between 2000 and 2010.

Population change between censuses ranged from a gain of 36.1 percent in Shelby County down to a loss of 16.1 percent in Lowndes County.

Alabama population growth was 7.5 percent.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 17

Most projected growth from 2010 to 2040 will occur in metro area counties.

Out-migration and aging will contribute to continued losses in rural counties.

Alabama’s population is forecasted to increase 16.5 percent.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 18

Small area population projectionsCBER can calculate population projections for areas down to the block group level. These are done on a contract basis.

Change between the two most recent censuses is used as a starting point.

A variety of other information, including building permits, infrastructure development, and recent or upcoming economic development are collected for the geographies to be projected.

ACS data, such as age of housing stock and income levels, is also used. Land area and housing density are examined.

CBER small area projections have been used for regional transportation plans and in socioeconomic impact studies for highway projects.

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 19

Check website for data

Projections are posted to CBER websitehttp://cber.cba.ua.edu

under Data, Maps, and Presentations.

They can also be accessed from the ASDC site’s Data section.

Detailed age/race/sex projections will not be posted due to their size, but will be available on CD from CBER for purchase.

Thank you!

Alabama State Data Center | Center for Business and Economic Research, The University of Alabama 20