And office vacancy has been falling steadily in Sonoma County. Net absorption totaled 345,000 square feet from the second quarter of last year, according to Cushman & Wakefield. The vacancy rate last month slipped to 10.9 percent overall down from 12.9 percent a year before. Particularly telling was the drop in class A vacancy to 9.1 percent from 18.1 percent and a slip in class B vacancy to 12.3 percent from 14.9 percent.Keegan & Coppin noted that overall office vacancy has been on a downward trajectory for a few years, falling to 13.8 percent in the first quarter from 15.0 in the first and second quarters of 2016.“Little pieces (of vacancy) are slowly getting filled in,” said Shawn Johnson, managing director of Keegan & Coppin. He pointed to the Santa Rosa submarket getting close to the 10.0 percent vacancy level. “There are not a lot of big deals running around, but there is enough to have reasonable activity.”