填空题

CHINA--China’s mainland replaced Japan as home to the world’s second largest online population by the end of last year, according to a national survey released yesterday.
The mainland’s online population which hit 59. 1 million by the end of 2002, up nearly 30 percent from the middle of the year, is larger than Japan’s latest figure of 54 million, said the China Internet Network Information Center.
The center predicted the number of net surfers in China would jump 46 percent to 86.5 million this year.
However, China still lags far behind the United States, which is home to 170 million Internet users. And China’s online population is only 4.6 percent of its total population. What is the online population of Japan