Google Inc has halved the amount of time it stores personal data gathered from its users’ Web surfing habits, a move aimed at improving its privacy policies, a company official said.

Google used to store such data for 18 months, but has now trimmed that duration to nine months.

Nicole Wong, Google’s deputy general counsel, told a meeting of computer industry privacy experts at Microsoft Corp’s Silicon Valley offices that her company planned to “anonymize” the computer addresses of its users more quickly.