Why should we have confidence in the population/demographic models used to support the plan?

The Plan Bay Area forecast was developed by ABAG with extensive assistance and peer review by a team of economists and other state agencies including the California Department of Finance.  The forecast uses demographic data from national and state sources, such as the U.S. Bureau of Labor Statistics, U.S. Census, and the California Department of Finance. It relies upon standardized forecasting methods to estimate the Bay Area's share of expected national employment growth and the detailed demographic characteristics (e.g., age, gender, race/ethnicity, etc.) of the region’s future population. The methodology for forecasting the region’s future population is based on natural increase of the existing population (births minus deaths) and expected job growth (which draws people to the region). A detailed description of the forecasting methodology is available in the Draft Forecast of Jobs, Population and Housing.

The forecast includes these inputs and is based on the best professional estimates of ABAG staff. In addition, although the SCS forecasts population growth out to 2040, by law the SCS must be updated every four years. This provides ABAG the opportunity to continually refine the assumptions and data used in its forecasts.