Given the charge by the County Board of Supervisors to plan regionally using the Service Planning Area (SPA) boundaries, in 1997 LAHSA commissioned a study by the Economic Roundtable, an independent non-profit public research organization. The study provided estimates, derived from analysis of income, employment and household composition using 1990 Public Use Microdata Sample (PUMS) data, of the percent of homeless people in each SPA. These allocations are used as targets for funding decisions for the Supportive Housing Program. The actual percentage of total funding received by SPA, however, depends on the number and quality of proposals submitted by agencies with programs to be located in that SPA.