Japan's monetary base expanded 3 percent in April from a year earlier, marking a 51st straight monthly increase, the Bank of Japan said Friday.

The margin of growth was bigger than that of the previous month for the second straight month.

This stable increase in Japan's monetary base is believed to reflect a rise in demand among financial institutions for cash on hand, with the government having abolished its unlimited refund guarantee on liquid deposits on April 1.

The average daily balance of the monetary base -- cash in circulation plus current-account deposits held at the central bank by financial institutions and Japan Post -- came to 111.556 trillion yen in the reporting month, the BOJ said.