WASHINGTON (Reuter) - The number of World Wide Web users has nearly doubled to 40 million people from a year ago, according to a survey released by Business Week magazine.

The poll of 1,000 U.S. households found that 21 percent of adults, or 40 million people, browse the Web, up from 21.5 million a year ago. An additional 12 percent use commercial online services, such as CompuServe Corp. or America Online Inc., the study said.

The survey also showed that the cyberspace gender gap is steadily shrinking. Women now make up more than two-fifths of Internet users, a group that includes Web viewers and other online users, up from 23 percent in September 1995.

The largest age group of Internet users are people in their 40s, who account for about a fourth of the cyberspace population. Nearly half of Internet users are 40 or older, the study showed.

The survey, conducted by Baruch College and Louis Harris & Associates Inc., was released Thursday.

Internet users are also fairly affluent, with more than two-fifths coming from households with incomes of more than $50,000 a year. Only 18 percent of Internet users make $25,000 or less each year.

The study also found that the Internet is dominated by whites, who make up 85 percent of Internet users. Blacks and Hispanics each only make up 6 percent of the cyberspace population