[TOKYO] The Bank of Japan's earnings fell 59.3 per cent in fiscal 2015 from the previous year, the first decline in five years, as gains in the yen reduced earnings on its foreign-currency denominated assets.
That compared with a 39 per cent increase in earnings in fiscal 2014, BOJ data showed.
The BOJ had 411 billion yen (S$5.15 billion) in net income in the fiscal year that ended in March, a statement showed on Friday.
The amount of Japanese government debt on the BOJ's balance sheet was 349.2 trillion yen at the end of fiscal 2015, up 29.4 per cent from the previous fiscal year, the central bank said.
If yields rose 1 per cent across the yield curve, that would lead to a 20.6 trillion yen loss on the BOJ's government debt holdings, a BOJ official told reporters.
A rising yen shaved 408.3 billion yen from the BOJ's earnings, the statement showed.
The BOJ returned almost all of its net income to government coffers, which is in line with central bank regulations, the statement said.
The central bank's capital adequacy ratio fell to 8.05 per cent in fiscal 2015 from 8.2 per cent in fiscal 2014, the central bank said. The BOJ prefers to keep its capital adequacy ratio at 8 per cent.
The BOJ is buying JGBs at an annual pace of around 80 trillion yen to lift inflation to 2 per cent sometime during fiscal 2017 and prevent the economy from returning to deflation.
These debt purchases are equivalent to more than twice the size of new debt the government sells to finance the budget deficit and have caused the BOJ's balance sheet to expand rapidly.