Here is a Bloomberg article on a Reis Inc. report that states that US office space in the fourth quarter had its first gain since 2007. Landlords added 2.5 million square feet of leased space. There is plenty of information in the article. The vacancy rate remained 17.6%, its highest level since 1993. Asking rents in the fourth quarter were lower than a year ago, but are higher than in the third quarter. Effective rents were also higher in the fourth quarter than in the third quarter. Calculated Risk also discusses the Reis report and has a cool graph showing historical office vacancies.