Mizuho Financial Group Inc., the nation's biggest banking group by assets, said Monday its group net profit for the last business year rose 54.2 percent from a year earlier amid the economic recovery and strong corporate earnings.

Mainly helped by a tax return, Mizuho's net profit for the year that ended March 31 came to 627.4 billion yen, a record profit since 2002 when a merger of three banks created Mizuho.

Its ratio of bad loans to total lending fell to 2.1 percent, with bad loans shrinking by about 800 billion yen to 1.4 trillion yen from the end of September.