Base Year Data: ES202 (unemployment coverage) data for 2000 was utilized as the primary tool to calculate employment at the zonal level. Individual business records containing physical location, number of employees and SIC code were geocoded through ArcView GIS and aggregated to the TAZ level. This data set was supplemented by other sources of data to complete the employment picture in the OKI region. Each zone’s employment was divided according to the SIC code into three classes (retail, office, industrial) based upon the potential for generating trips.

Future Year Data: For future year employment projection, calculation was first made of the employment at the regional level. At the regional level, employment is a calculation of the region’s employed labor force minus workers who live in the region but commute out to work, plus workers who live outside the region but commute in to work. The regional total was disaggregated first to the county level based on historic trends and expected changes in the county’s share of the region’s employment and then to the TAZ level.