Spending on office buildings, which has dropped 47.5 percent since the September 2008 record-spending high, is nearing a 13-year low, according to the Institute for Trend Research. Permits for new-office construction have dropped 26.7 percent just since last December. Office vacancy rates in the second quarter of 2010 increased to 17.4 percent, the 10th consecutive quarterly rise. Construction of office buildings is projected to close 2010 at nearly 32 percent below 2009.