The monetary base in Japan was up 3.6 percent on year in May, the Bank of Japan said on Tuesday - coming in at 510.808 trillion yen.
That's up sharply from the 3.1 percent increase in April.
Banknotes in circulation gained 4.6 percent on year, while coins in circulation added an annual 2.3 percent. Current account balances rose 3.4 percent on year, including a 3.1 percent gain in reserve balances.
The adjusted monetary base surged an annual 16.3 percent to 507.162 trillion yen.