Calculating the worldwide growth of the Web remains largely a matter of guesswork, more than a decade after the commercial Internet exploded into popular view.

Seeking to standardize global online measurements, comScore Networks Inc. introduced on May 5 a new global survey with an estimate that 694 million people, age 15 or higher, used the Internet during March, or around 14 percent of adults.

The survey, called the comScore World Metrix, estimates there are 168.1 million users across four Asian countries -- China, Japan, India and Korea -- or nearly 25 percent of the total online population. By contrast, the United States is home to 152 million users, or 22 percent of the world's Web users.

The monthly study seeks to balance out the traditionally U.S.-centric art of Internet measurement, since market research data in the world's largest market is more widely available.

ComScore, a Chicago-based traffic measurement firm, known for its surveys of U.S. users, said it had surveyed 2 million Internet users representing a cross-section of countries with 99 percent of the world's population -- representing one of the most universal estimates based on a consistent methodology.

Most existing global surveys are a hodgepodge of national statistics stitched together with extrapolations on computer use in regions where data is sketchy. Some compilation efforts have estimated numbers in excess of 1 billion users.

Among major Web sites, Web search leader Google Inc. and Yahoo Inc., a diversified network of Internet media sites, are neck and neck in terms of total worldwide audiences, the study found.

Google ranked No. 2 in terms of global Internet audience with an estimated 495.8 million users in March, compared with No. 3-ranked Yahoo, with 480.2 million users.

Microsoft's collection of sites attracted the largest global audience with 538.6 million, which includes not only its consumer Internet audience for MSN, instant messaging and its free e-mail service, Hotmail, but also traffic to Microsoft.com for software downloads and other non-consumer activities.

EBay Inc., Time Warner, Amazon.com Inc., the user-contributed Wikipedia and IAC/InterActiveCorp.'s Ask network rounded out the top rankings, according to the comScore World Metrix survey.

By contrast, Nielsen//NetRatings, a rival U.S. Web traffic measurement firm, offers a global estimate of active home Internet users of 317 million in March. China Internet Network Information Center (CNNIC), a government-backed Internet organization, estimated there were 111 million users of all ages in an annual statistical report issued in January 2006.

ComScore estimates 74.7 million adult Web users in China, a figure that excludes public computer use in Internet cafes -- a popular means of online access, especially among young people.

Japan ranks No. 3 with 52.1 million, Germany No. 4 with 31.8 million users and Britain nearby at 30.2 million, according to the comScore.

( www.financialexpress.com)