San Francisco -- Though CEOs feel less confident in the overall Bay Area economy, conditions appear to be better in the Silicon Valley counties of Santa Clara and San Mateo, according to the latest Bay Area Business Confidence Index. The latest index fell five points since last quarter, down to 55 out of 100. Only one third of the 509 CEOs and top executives surveyed between July 12 - August 2 say the local economy will improve in the next six months, while 21% predict a decline. In Santa Clara and San Mateo counties, however, approximately half of the CEOs surveyed said that local economic conditions are either moderately or substantially better than they were six months ago, the most optimistic sentiment in the Bay Area. The best place to find a new job appeared to be San Mateo County, where half of respondents plan to enlarge their work force.