The key gauge of the nation's economic health stayed below the boom-or-bust line of 50 percent in June for the sixth-straight month, providing more evidence of economic contraction, the government said Monday.

The index of coincident indicators came to 31.3 percent in the latest reporting month, with all production-related component indicators showing negative moves, the Cabinet Office said in a preliminary report.

Six months is the longest the index has remained below 50 percent since a 17-month stretch between August 1997 and December 1998, when the economy was in recession.