Japan may exempt home purchases from any increase in its sales tax, or reduce the amount of increase, Finance Minister Jun Azumi said. Prime Minister Yoshihiko Noda aims to double the 5 percent sales tax by 2015 to boost revenue and contain a public debt burden twice the size of Japan's annual economic output. The legislation needs approval of parliament, and Azumi and two deputy ministers are today meeting with taxpayers in three cities to explain the need for a tax increase. Raising the sales tax would be the first step toward reducing the nation's public debt and reforming finances, Azumi said today in the quake-stricken northern city of Sendai.