Overall advertising spending was down 1.4 percent during the first half compared to the same period last year, according to figures released today by the Nielsen Company’s Monitor-Plus service.Ad spending during the period was down 8 percent for b-to-b magazines and down 3.1 percent for national magazines. Local magazines posted a slight gain of 0.3 percent over the same period in 2007.Nielsen’s Monitor-Plus figures differ slightly from the same-periodnumbers from the Publishers Information Bureau and the BIN report.According to PIB, ad revenues for the first half were down 2.8 percent.BIN (which tracks b-to-b titles) had revenue declining more than 6percent for the first half.Among the 19 media categories tracked, cable TV posted the largest ad spending gains, up 8.1 percent over the first half last year. Spot radio was the biggest decliner, down 10.1 percent. Continuing its declines, national newspapers saw ad spending fall 8.1 percent during the period. Local newspapers were only slightly better, posting a 7.3 decline.Much of the ad declines could be due, in part, to skyrocketing gas prices. The automotive ad category accounted for $5.33 billion, down 8.01 percent from $5.79 billion during the first half of 2007. The pharmaceutical (-4.76 percent), and motion picture (-4.64 percent) ad categories also saw declines.