The tertiary industry activity index rose 1.1 percent in October from September for a third straight monthly increase, the government said Monday.
The index came to a seasonally adjusted 110.2 against the 1995 base of 100, its highest level since January 1988, the Ministry of Economy, Trade and Industry said in a preliminary report.
The indexes for the transport and communications, financial services and insurance, real estate, and wholesale and retail sales sectors gained in the reporting month.
The index for the mobile communications sector jumped 51.3 percent, making it the largest contributor in pushing up the overall index of tertiary industry.
But a METI official said the data must be viewed with caution because there was no evident reason for such a surge in the sector in October and the figure was apparently magnified as a result of seasonal adjustment following a sharp drop in September.
The securities sector climbed 8.4 percent on active transactions in stock markets in October, and retail sales of apparel and accessories increased 4.4 percent as the seasonal temperature was favorable for clothing sales, the official said.
On the other hand, the services and utilities sectors both dropped 1.9 percent.