Last month the Metropolitan Washington Council of Governments approved an update to the Cooperative Forecast of employment households and population. The forecast is primarily used for transportation modeling where it determines how many people are likely to live in each part of the region and where they are likely to travel. This tool also lends insight to other infrastructure and service planning initiatives because it is a best guess of how much growth is likely to occur and where it is likely to occur.

The forecast is developed through a top-down bottom-up process. Planners at the Council of Governments conduct a macroeconomic analysis that determines how many jobs households and population the region is most likely to have at five year intervals thirty years in the future.

Then each jurisdiction analyzes a combination of local and regional data to forecast their own jurisdiction’s jobs households and population at the same intervals. This part is called the large area forecast.

Next the large area forecasts are combined and the totals are compared to the macroeconomic analysis. If the totals are within three percent of each other the large area forecasts are approved by local government planners on COG’s Cooperative Forecasting Data Subcommittee and submitted to the COG Board of Directors for approval. Alternatively if the large area forecasts vary from the macroeconomic model by more than three percent the committee reviews the findings and methods from each jurisdiction to identify changes necessary to reconcile the two data sources.

Each jurisdiction uses its large area jurisdictional forecast to generate a small area forecast. These forecasts are created using Traffic Analysis Zones which correspond to land use patterns. Local planners use a combination of local planning zoning permitting and demographic trends to assess what the jobs households and population is most likely to be in each zone at each five year interval. Then the small area forecasts are reviewed by the local planning directors for consistency with the large area forecasts and finally submitted to the COG Board of Directors for approval.

Click Here to Download the Forecast

Earlier Post Detailing Major Findings from the Modeling Release of Round 8.2 of the Cooperative Forecast from February 2013