It seems the tough economy is hitting ad networks after all… Pubmatic, which sells software optimization tools to ad networks, finds that prices for remnant ad nets have not moved much in the past three months. On average, websites’ ad inventory prices have fallen by less than one percent from $0.37 in May to $0.36 in June. While Pubmatic’s figures do not count ad networks’ share of ad spend as well as inventory sold directly by publishers to ad agencies or advertisers, some categories experienced some significant drops in value. Small size sites had the largest decline, coming in $0.81 for June, down from $1.13 the previous month. By vertical, news and gaming also fell, sliding $0.62 and $0.20, respectively. Entertainment avoided the trend, rising $0.11 from $0.29 in May to $0.40 in June. Release.

—Ad budgets revised downward in the U.K.: In line with many other reports over the past few weeks focusing on the U.S., the U.K.‘s ad market looks pretty dim too these days. The Institute of Practitioners in Advertising and Markit Economics, in their Q2 Bellwether report, say that ad spend going to to online marketing and search in the U.K. were at its slowest pace in five years, ClickZ reported. Digital expenditures up just 6 percent in Q2 compared with a 21 percent rise in Q1 from Q407. For the 250 marketers asked about spending increases, 19 percent said online ad spend rose in Q2;  27 percent said the same in Q1. Also, 12 percent spent less online in Q2, while only 5 percent said they pulled back in Q1. On the bright side, the IPA release noted that all marketing sectors saw budget cuts with the exception of the internet. That said, Q2 saw the smallest upward revision since 2003.

• Magna’s Coen Revises Online Ad Spend Forecast Downward; Sees 12 Percent Gain In ‘08
• Global Online Ad Revs To Grow 19.5 Annually To 2012: PwC
• Online Ad Revenue Growth Rates Declined From Q4 To Q1: IAB
• Display Ads Grew 8.5 Percent In Q1, Down From Last Year’s 16.7 Percent Gain: TNS