Capitalization rates, used by real-estate investors to measure the annual return of income-producing properties, declined for many property types in 2013, according to data from Real Capital Analytics in New York. Meanwhile, the spread between cap rates and yields on 10-year Treasury notes narrowed. The average cap rate for all property types was 6.74% last year, down from 6.76% in 2012. Cap rates fell fastest for office buildings, which had an average cap rate of 6.93% in 2013 compared with 7.15% in 2012. Wall Street Journal 1/29/14.