NEW YORK CITY (By Antone Gonsalves, Tech Web)

In December, AOL, a division of Time Warner Inc., experienced a 15 percent drop from the same month a year ago to 16.6 million page views, ComScore Networks said. Yahoo Inc., on the other hand, jumped by 20 percent to 36.2 million page views, and Microsoft Corp.'s MSN rose 5.6 percent to 17 million.

ComScore does not include Google Inc., which the firm classifies as a search engine.

AOL, which recently changed its brand name from America Online Inc., appears to be experiencing some pain in its move from a proprietary Internet service provider with a large number of dialup subscribers to an entertainment portal on the public Web that makes money through online advertising.

In making the transition, the company has gone from an environment in which subscribers click on pages within a walled site to one in which they can jump quickly to a different property, Peter Daboll, president and chief executive of ComScore said.

"(Also) they're seeing some decline in subscribers and in people using the proprietary site," Daboll said. "Those (people) may have been heavier users of AOL."

Overall, the portal market in December experienced a 16 percent increase in page views compared to a year ago to 461.2 million, ComScore said. Market growth is expected to continue as the industry expands to markets outside the United States, and improves its offering of Web services, such as photo sharing, social networking, blogging and personalized homepages, Daboll said.