Despite a troubled economy, office space in downtown Rochester is in greater demand than it was 12 months ago, says a new report by the Rochester Downtown Development Corporation. The nonprofit consulting firm has been tracking the downtown real estate market since 1983. | The report looked at 111 buildings and more than 10.7-million square feet. After removing single owner-occupants and government office buildings, the downtown vacancy rate is 19.2 percent. | The tighter vacancy rate is due to renewed interest in downtown, the report says, with 10 companies moving from the suburbs to the city over a 12-month period. That raises the question: what is happening regionally? | "The end game is to improve regionally," says Heidi Zimmer-Meyer, RDDC's president. "If all we're doing is borrowing from Peter to pay Paul, we haven't accomplished very much. We've got to grow our existing companies and add new companies." | Angelo Nole, executive vice president of CB Ellis, one of the country's largest real estate firms, is optimistic about metro Rochester. | "More office space is being leased faster than it is coming on the market," he says.