L.A. Office Boom Slows: The growth rate in the once-booming office space market in Los Angeles County plunged by 40% in 1990, reflecting a nationwide real estate slump, Grubb & Ellis reported. "We have gone from the incredible growth of the late 1980s to fairly good growth," said Dennis Macheski, a researcher with the real estate services firm. "But Los Angeles County is still quite good compared to the rest of the nation." The San Francisco-based firm said 4.3 million square feet of office space in Los Angeles County were leased in 1990, compared to 7 million square feet in 1989. It also said the office vacancy rate for the county stayed at 15% during both years. Macheski predicted that the vacancy rate will rise this year and in 1992, then drop in 1993 because of a slowdown in new construction, brought on by banks' lack of willingness to provide financing for projects.