The key gauge of economic health came to zero in August, remaining well below the boom-or-bust line of 50 percent for the eighth straight month, the government said Friday in a preliminary report.

It was the first time since March 1998 that the key gauge has stood at zero, the Cabinet Office said.

In addition, the July reading of the diffusion index of coincident indicators, which measures the current state of the economy, was revised to 10 percent.