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Oklahoma Population Projections Through 2075. Presented by: Steve Barker Policy, Research and Economic Analysis. Today’s Topics of Discussion. Common projection methodology Oklahoma’s population trends Projections for Tulsa MSA counties Questions and answers. Standard Projection Formula.
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Oklahoma Population Projections Through 2075 Presented by: Steve Barker Policy, Research and Economic Analysis
Today’s Topics of Discussion • Common projection methodology • Oklahoma’s population trends • Projections for Tulsa MSA counties • Questions and answers
Standard Projection Formula State level projections start with 2010 Decennial Census counts and follow forecasting routines developed by the US Census Bureau: + - + = + - + = -F- *Based on fertility rates and # of women of child bearing age -A- Population in the current year -B- Births in the current year -C- Deaths in the current year -D- Net migration -E- Population projection for the next year -E- Population projection for the year -F-Births in the next year* -G-Deaths in the next year -I- Population projection for the next year -H- Net migration
Who is included in projections? Everybody! • All civilian residents living within the state • US Armed Forces stationed within Oklahoma • Prisoners, including out of state prisoners held at private prisons located within the state
Projection of births and deaths Birth and death rates assumed to remain constant.
Oklahoma’s net migration history • 1970 to 1983: Oklahoma boomed • Peak annualgrowth of 3.6% in 1982 • Double digit annual percentage growth in some less populated counties • And then came the oil bust… • 1987: state’s annual population growth rate dropped to -1.3%.
Net migration: what’s the norm? • 1960 to 2011: Oklahoma’s population gain due to net migration averaged around 10,000 people annually • Swings from +80,500 in 1982 to -61,000 in 1987 • 1990 to today: Oklahoma’s average annual net migration gain just under 15,000
County projections handled differently • For 64 counties, used straight linear regression trendline formulas • Based on population patterns from 1960 to 2011 • For 13 counties, all in western Oklahoma, straight linear regression formulas gave unrealistic results • Alfalfa, Cimarron, Dewey, Ellis, Grant, Greer, Harmon, Harper, Kiowa, Roger Mills, Tillman, Washita and Woods • For these 13 counties, a curved, or power, trendline was judged to be a better fit
Matching up two methodologies • Census Bureau population estimates based on birth, death and migration data • They have situations where sum of parts doesn’t equal the expected whole • They use a balancing figure that effectively serves as a “margin of error” • This report used similar approach • Between 2010 and 2075, the required adjustment averaged 0.2% of each year’s total population.
Population Growth: 1960 to 2010Totals Source: US Census Bureau’s Decennial Census and Population Estimates Programs
Year Over Year Population Growth: 1960 to 2010 Source: US Census Bureau’s Decennial Census and Population Estimates Programs
With all that said, predicting the future is a bit like this… So wish me luck!
For more information: www.okcommerce.gov/data Email: steve_barker@okcommerce.gov Twitter: @okdatacenter