E-2. California County Population Estimates and Components of Change by Year — July 1, 2020-2023

December 2023

OFFICIAL STATE ESTIMATES

Contents

This report presents preliminary state and county population estimates for July 1, 2023, revised estimates for July 1, 2020, July 1, 2021, July 1, 2022, and components of population change.

Highlights

California’s population declined by 37,200 between July 1, 2022 and July 1, 2023, to total 39.11 million, according to official population estimates released today by the California Department of Finance

The 0.10-percent (37,200 person) decline reflects the ongoing recovery in California’s population growth following the COVID-19 Pandemic. “Excess” deaths continue to drop from their peak in 2021 and immigration levels have largely recovered since the end of stringent rules imposed early in the COVID-19 response.

The population decline during the year ending July 1, 2023 is a fraction of the drop during the first full fiscal year of COVID-19. In 2020-2021, California’s population declined by 0.75 percent, or 295,000 persons, mainly due to significant reductions in natural increase and foreign immigration.

Leading factors contributing to population trends in the year leading up to July 2023 include:

  • Natural increase—births minus deaths—increased from 66,800 in 2020-2021 to 107,300 in 2022-2023. Births declined from 411,900 persons to 409,200 persons and deaths declined from 345,300 persons to 301,900 persons.
  • Foreign immigration recovered to pre-pandemic levels, with a net gain of 115,900 persons in 2022-2023. That followed two years of negative net foreign immigration for the years ending in July 2020 and July 2021.
  • Domestic out-migration slowed in 2022-23, to a net domestic migration loss of 260,400 people.

Natural increase—births minus deaths—added 107,300 people from 2022 to 2023 with 409,200 births, and 301,900 deaths. Births were down from 423,400 in the year ending July 1, 2022, while deaths were down from 318,500.

For nearly 20 years California has experienced negative net domestic migration, in which the number of people moving out of the state in a year exceeds the number moving in. Since 2016, net domestic outmigration has exceeded net international migration, leaving natural increase as the only source of population growth. Natural increase is constrained by continuing fertility declines and increased deaths from an aging population.

Net international migration to California reached 115,900 people in the year preceding July 2023, nearing Pre-COVID-19 pandemic levels. While net international migration added population during this period, negative domestic net migration still outweighed these gains, resulting in an overall net migration loss of 144,500 residents.

Methodology

The state and county population are independently estimated using population change models benchmarked on official decennial census counts. The state population is estimated using the Driver License Address Change method. County population proportions are estimated using the average of three separately estimated sets of proportions. The final distribution of proportions is applied to the independently estimated state control.

State Estimate. The state population is estimated using the Driver License Address Change (DLAC) Method. This composite method separately estimates the population under age 18, 18 through 64, and 65 years and older. Administrative records such as births, deaths, driver license address changes, tax return data, Medicare and Medi-Cal enrollment, immigration reports, elementary school enrollments, and group quarters population are among the data used in this method. All data used to develop these estimates are in summary tables and do not reveal the identity of any individual.

County Estimates. Most of county populations estimates result from averaging the first three methods below. We use a Vital Statistics Method in nine counties with 65,000 populations or less.

DLAC Method. A modified version of the state Driver License Address Change (DLAC) method is used for counties. County proportions of the state total result from changes in county population values for births, deaths, school enrollment, foreign and domestic migration, medical care and medical aid enrollments, and group quarters population.

Ratio-Correlation Method. This method models change in household population as a function of changes in the distributions of driver licenses, school enrollments, and housing units. Estimates of county group quarters are added.

Tax Return Method. County proportions are derived by the U.S. Census Bureau using matched federal income tax returns to estimate inter-county migration along with vital statistics, group quarters, and other information for the population aged 65 and over.

Vital Statistics Method. County population estimates result from changes in county population values for births, deaths, and group quarters population.

For the first time, this data series uses the 2020 Census as the benchmark population following the release of the 2020 Census Demographic and Housing Characteristics file in May 2023. This estimate reflects revisions to the preliminary July 1, 2022 state and county estimates released in January 2023, with updated data on domestic migration from the Internal Revenue Service.

Data Considerations

Sources. Data used in estimation models come from administrative records of numerous state and federal departments and agencies. Timeliness and coverage in these series vary. Corrections, adjustments or estimates may be made while preparing the estimates.

Accuracy. In general, estimates become less precise as the time from the last census increases. Data and models used to produce population estimates are subject to both measurement and non-measurement errors. This results in imperfect correlation between the data used to estimate the population and actual population change. The data and estimating models have been thoroughly tested with decennial census results that provide benchmarks for the estimates series. Data and methods are further refined and modified throughout the decade.

Acknowledgments

Phuong Nguyen produced the state and county estimates and prepared this report. Andres Gallardo produced the birth and death data. Douglas Kuczynski and John Boyne collected and prepared the group quarters data. Alex Alvarado produced the school enrollment projections. John Boyne validated input data, formulas, and methodologies used in the current state and county estimates series.

Suggested Citation

State of California, Department of Finance, E-2. California County Population Estimates and Components of Change by Year, July 1, 2020-2023. Sacramento, California, December 2023.