The key index of indicators designed to show the current state of the economy rose in December to its highest level in more than five years as companies boosted production and tried to increase employment as their profits recovered, the government said Friday.

The index of coincident indicators, such as industrial output, retail sales and new job offers, climbed 1.0 point from the previous month to 111.7, up for the fourth straight month, against the 2010 base of 100, the Cabinet Office said in a preliminary report.

The figure was the highest since May 2008, before the bankruptcy of Lehman Brothers Holdings Inc. in September that year triggered the global financial meltdown and dragged down Japan's economy, an official at the office said.

The government left its basic assessment of the coincident index unchanged from the previous month, saying this indicates the economy is "improving."

The index of leading indicators, which predicts developments in the coming few months, also increased for the fourth consecutive month, up 1.1 points to 112.1, the biggest since February 2007, as business confidence among smaller firms improved.

The index of lagging indicators, measuring economic performance in the recent past, gained for the second straight month, up 1.0 point to 115.1, the highest since December 2008.

In December, industrial production marked the first rise in two months, aided by active spending ahead of the sales tax hike to 8 percent in April, while job availability improved to its highest level since September 2007.