BUSINESS BRIEFING : SOCIAL NETWORKING : Twitter sees 8% drop in U.S. users

The number of Americans using Twitter dropped 8% in October from September, marking the second monthly decline for the social-networking site this year, according to research firm ComScore Inc.

Twitter Inc., the No. 3 social-networking site in the U.S., had 19.2 million users in October, ComScore said. The company had growth of less than 1% in September and declined in August. October’s number was still up more than 13-fold from the year-earlier period.

The month-to-month drop contrasted with a 2% increase for users of Facebook Inc., the most popular social network. Facebook had 97.4 million U.S. users last month, more than double the amount a year earlier, ComScore said. News Corp.’s MySpace, which ranks second among U.S. social-networking users, fell 2.5% from the previous month.