New York—Total combined local and national radio ad sales were up 1% in May compared with May 2005, according to the Radio Advertising Bureau’s Ad Sales Index. Local radio sales were up 1% in May, while national radio sales were down 1%, according to RAB. Nonspot revenue was down 1%, and total combined spot and nonspot revenue was up 1%. Year-to-date, total combined local and national radio sales were down 1% compared with the same period in 2005, the report found. Also year to date, local radio ad sales were down 2%, national sales were flat, nonspot revenue was up 6%, and total spot and nonspot revenue was down 1%.