The study described in this report was designed to determine student enrollment trends and the service area of Arizona's Phoenix College (PC). Headcount and full-time student equivalent (FTSE) data were collected for fall semesters from 1985 through 1989. The average yearly change in enrollments was calculated and presented in table and graph formats. To determine the PC service area, enrollment totals by zip code were collected for fall 1989 from which a map of the service area was drawn. It was revealed that PC day headcount increased an average of 4.04% per year, and day FTSE increased on the average of 1.92% per year. Evening headcount declined an average of 1.38% per year, and evening FTSE declined an average of 1.76% per year. Zip code analysis showed that approximately 70% of the students at PC lived within an area less than six miles in radius, and enrollment from zip codes that include major thoroughfares extended beyond the six-mile radius. It was concluded that the overall average enrollment trend over the past 4 years at PC has been stable; average growth was approximately 1% per year. Additional enrollment trend studies are recommended, including an examination of trends within demographic subdivisions such as age, gender, and ethnic identity. Contains 14 references. (GLR)