Japan big manufacturers' mood worsens in January-March - government

TOKYO (Reuters) - Big Japanese manufacturers' sentiment worsened sharply in January-March, a government survey showed on Friday, suggesting the economy has lost momentum at the start of the year.

The business survey index (BSI) of sentiment at large manufacturers stood at minus 7.9 in January-March, swinging from plus 3.8 in October-December, according to the joint survey by the Ministry of Finance and the Economic and Social Research Institute, an arm of the Cabinet Office.

The BSI measures the percentage of firms that expect the business environment to improve from the previous quarter minus the percentage that expect it to worsen.

(Reporting by Izumi Nakagawa and Stanley White; Editing by Chang-Ran Kim)