The average cost for a primetime spot declined by 0.7 percent to $132.970 in the 2006-07 season from the previous year, according to figures from NetCosts, which uses real media buying data from national advertisers that spend a combined $12 billion per year.

According to the NetCosts data, NBC, which suffered a steep ratings drop during the season, also saw its ad prices slide 16.2 percent. Fox, which won the ratings race among adults 18 to 49, saw its ad units jump in prices by 25.8 percent. ABC’s spots rose 3.8 percent, while CBS’s spots were down 3.7 percent.

NetCosts is a service of SQAD, based in Tarrytown, N.Y. The SQAD numbers were analyzed and released by TargetCast tcm, an independent media agency.