In February, Microsoft's Bing continued its slow but steady rise, grabbing a slightly higher chunk of the U.S. search engine market, according to data released Friday by ComScore.

Among the three top search engines, Microsoft's share of the search market rose to 13.6 percent, up half a percentage point compared with January. In comparison, Google lost two-tenths of a percentage point but still dominated the market with 65.4 percent of all searches in February, while Yahoo's share stayed flat at 16.1 percent.

Though Microsoft may have picked up more share, the number of searches conducted at Bing fell to 2.1 billion, down 5 percent compared with the previous month. But those numbers were still better than those at the other search engines. In February, Google saw the number of searches at its site fall by 9 percent to 10.1 billion, while Yahoo also witnessed a 9 percent drop with its total number of searches declining to 2.5 billion. ComScore said the lower number of searches last month is simply because February is a shorter month than January.

Overall, Internet users conducted around 15.4 billion explicit core searches last month, compared with 16.9 billion run in January.

As always, the results focused on the total number of explicit core searches--search terms manually entered on a Web page. ComScore also looked at the number of "powered by" searches, those conducted both at a search engine's own site and at other sites.

Google's "powered by" share of searches at its own site and those at AOL and Ask fell to 68 percent, down from 68.2 percent in January. Microsoft's "powered by" share of searches at Bing and at Yahoo rose to 26.2 percent, which was 25.6 percent the prior month.