The downtown office vacancy rate rose.

Although the downtown Los Angeles rate increased to 10% in the second quarter from 8.4% in the first quarter, it is much lower than the 15% to 20% vacancy rate that is expected to be reached when several new office buildings are completed in the next several months, according to a survey by Grubb & Ellis Commercial Brokerage Services. The downtown vacancy rate was 10.79% during the second quarter of 1984.