Online adspend growth is slowing down according to Universal McCann's director of forecasting, Robert Coen, who for 2005 predicts a 15 percent year-over-year increase in online ad spending, which he expects will reach $7.8 billion, ClickZ reports. Coen notes in his report that online advertising revenue - excluding search and affiliate marketing - was up 8 percent in the first quarter of this year compared with the first quarter of 2004, which had grown 28 percent over the first quarter of 2003.

Coen says that some display advertising money might be flowing into search or other performance-based marketing, which are not included in his forecast. Nevertheless, his projections for online adspend growth were nearly twice as high as those issued yesterday by TNS Media Intelligence.

Coen also revised downward his predictions about 2005 spending levels in the U.S. and worldwide for all advertising. He now expects U.S. advertising to grow 5.7 percent in 2005, down from an earlier estimate of 6.4 percent. Total worldwide spending will come in at 5.8 percent growth, Coen predicts. Earlier, he had expected a 6.1 percent growth rate for 2005. But his 2006 outlook is better. He expects a 5.8 percent growth rate for U.S. advertising and 5.7 percent growth worldwide.