A quarterly business and investment survey released Wednesday by the Economic Planning Agency shows confidence among Japanese companies about the domestic economy improved considerably in the April-June period.

The agency's Business Survey Index for the period stood at a seasonally adjusted 10 in the April-June quarter, up from 4 in the January-March period this year.

This is the fourth consecutive quarter in which the index has remained in the positive column, and a level of 10 was last seen in the October-December period of 1996.