"It could be in response to policies to tighten investment last year," he said, warning, however, against reading too much into statistics from just a single month.
The Chinese government spent most of 2004 trying to slow down the economy in order to eradicate bottlenecks, especially in the energy and transportation sectors.
It had only limited success in this endeavour as the economy still grew at the heady rate of 9.5 percent, the highest level since 1996.
Significantly, the industrial output figure reported Friday by the statistics bureau was adjusted for the Lunar New Year holiday, which fell in January last year and in February this year.
If not adjusted for the larger number of working days in January 2005, the growth rate would have been 20.9 percent, the bureau said.
"On the face of it, the January figure looks extremely worrying but it's very difficult to adjust for seasonality," said John Cairns, an analyst with IDEAGlobal in Singapore. Among recent statistics showing the economy is still roaring ahead, exports jumping 42.2 percent in January from a year earlier.
Overall, overseas demand was a large factor in fueling activity along Chinese assembly lines in the first month of the year, the statistics bureau reported.
It said exports of industrial products alone rose 31.2 percent from last year, even when adjusting for the Lunar New Year period.
China has been accused of keeping its export machine humming by leaving its currency, the yuan, at an artificially low rate, pegged at 8.28 to the US dollar for the past decade.
The data also showed large enterprises managed to sell 97.7 percent of their production, suggesting that the slowdown in industrial output was not the result of weakening demand.