A key gauge of the current state of the economy moved above the boom-or-bust threshold of 50 percent in May, the government said Thursday, underscoring the steady growth.

The index of coincident economic indicators was 77.8 percent, down from a revised 80.0 percent in April but moving above the threshold for the second straight month, the Cabinet Office said in a preliminary report.

A reading above 50 percent is considered a sign of economic expansion and a figure below that line is seen as a sign of contraction.

Of the 11 economic indicators used to calculate the coincident index, nine were available for the preliminary report, of which seven posted positive readings, the report says.

Of the seven, year-on-year rises in sales by wholesalers, sales data for small and midsize companies and the job offers-to-seekers ratio hit the highest level on record.

The index of leading indicators, predicting economic developments about six months down the road, came to 75.0 percent, up from a revised 54.5 percent and moving above the 50 percent line for the second consecutive month.

The index of lagging indicators, designed to measure economic performance in the recent past, was 75.0 percent, down from a revised 100.0 percent but staying above the key line for the eighth straight month.

The diffusion indexes compare the levels of various economic data for a reporting month with levels three months earlier.