Chinese portal Sina Corp.'s quarterly profit tumbled 75 percent on relatively small revenue for its microblog service.
Sina said Wednesday it earned $2.4 million in the three months ending Dec. 31, compared with $9.3 million a year earlier. Revenue rose 4 percent to $139.1 million.
Online advertising revenue rose 7 percent to $110.7 million. Non-advertising revenues, mostly from the company's popular Sina Weibo microblog service, rose 181 percent but stood at just $10.6 million.
"2012 was a year of investment for Sina," said chairman Charles Chao. "In 2013, we will continue to improve user experience and expand the scale of Weibo monetization, while turn our focus to mobile Internet for all of our major product lines."
Sina offers online and mobile media as well its microblog service.