The current debate about charter schools' effects on school district finances hinges on enrollment loss. Critics claim that the surge in charter enrollment in California since 2000 has driven enrollment loss statewide--cutting districts' income more than their costs, especially in cities where many students attend charter schools. State officials are under pressure to cap the growth of charter schools as a way of stabilizing district enrollments, and thus finances. This brief examines state and district data on district and charter school enrollment trends over the past 10 years. We pay particular attention to Los Angeles, Oakland, and San Diego, where claims of harm done by charter enrollment growth have been made most often. The brief makes three points: (1) Surges and declines in K-12 enrollment have long been a fact of life in California districts. Statewide numbers of school-age children are currently falling and will continue to do so; (2) The growth of charter schools cannot account for all of the enrollment loss experienced by urban school districts; and (3) Charter school enrollment is not currently a major factor in continued district enrollment decline. [To view "Do Charter Schools Cause Fiscal Distress in School Districts?" see ED595169 and "Do the Costs of California Charter Schools Outweigh the Benefits?" see ED595193.]