Californians vacationing in their home state by car are reported to be helping the state recover from the tourism slump that followed the September eleventh terrorist attacks. State campgrounds had an immediate 20 percent jump in reservations after September eleventh. Lowered camping fees could bring an overall ten percent increase in attendance at state parks this year, totaling about 90 million people. It had been predicted that summer travel in California this year would be down about nine percent from last year. But state tourism officials now think the decline will be closer to five percent.