Take electricity consumption, for example. It was famously touted by Premier Li Keqiang in 2007 as a good measure of China's economic pulse, compared to "man-made" gross domestic product data often massaged by officials trying to prove themselves.
Power consumption in the first 20 days of January rose a mere 2 percent from a year ago, according to China's economic planner, the National Development and Reform Commission. Jia Fusheng, a commission official who disclosed the figure, conceded that the rate is "certainly quite low", but suggested the Lunar New Year holiday and a relatively warm winter may have been the cause.
State Grid Corporation of China, which sells electricity to 85 percent of China's population, is not so sanguine. It expects business to slow this year as a wobbly economy and growing environmental awareness temper demand.
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Electricity consumption should rise between 6.5 percent and 7 percent this year, State Grid said on its website in January, down from last year's 7.5 percent increase.
"It's a good indicator of activity in the manufacturing industry," said Haibin Zhu, a JPMorgan economist. "On the ground, the sentiment that we got by talking to factories was not upbeat in January."
It's actually healthy
Even those skeptical that power consumption paints the true economic picture find other reasons to be cautious.
Prices for cement, steel and iron ore - the main materials for constructing buildings and railways - are all falling, partly because demand is dropping on slower state investment.
Just last week, steel prices slumped to a record low of 3,380 yuan a tonne and iron ore pricesdrooped to a seven-month trough. Cement prices hit a two-month low of 350 yuan a tonne in January, according to China Construction Bank.
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Suspended construction work during the winter and fierce competition between steel mills that have sparked brutal price wars have dented prices. But so has weaker final demand.
ArcelorMittal, the world's largest steelmaker, predicted last week that China's steel consumption growth would slow this year even as prospects improve in the United States and Europe.
Analysts think much of the drop in demand is the result of provincial and local governments, who having chalked up at least $3 trillion in debt, meeting stricter orders from Beijing to cut graft and frivolous investment, including building flashy offices for themselves.
Shrinking budgets have even affected New Year revelry. Retail sales over the Lunar New Year holiday rose at their slowest rate in five years at 13 percent as officials scrapped lavish celebrations. Prices of sea cucumber, a delicacy that can cost several thousands of yuan, are at their lowest in over four years, said Dong Tao, an economist at Credit Suisse.
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"State executives and local officials appear more worried about their jobs than investment," Tao said.
And rising interest rates are making things worse. Alarmed by the speedy rise in debt levels in recent years, China's central bank has nudged short-term rates higher to try to curtail risky lending. The seven-day bond repurchase rate, the benchmark rate for short-term lending, is off near 9 percent highs seen in December, but is still up about 1 percentage point from a year ago at 4.4 percent.
The growing signs of weakness have convinced analysts such as Tao from Credit Suisse to shave his first-quarter GDP prediction to 7.3 percent, which would be the slowest pace since the global financial crisis, from 7.7 percent on an annual basis. The economy grew 7.7 percent in the fourth quarter.
But to Mark Williams at Capital Economics in London, more signs of slack is good news, not bad. An orderly slowdown where wasteful spending is reduced and growth is sliding towards 7 percent is just what China needs as part of reforms to lift consumption at the expense of investment.
"It's a healthy correction and should be welcomed," said Williams.