Feb. 21 -- Property prices rose in most Chinese cities in January after the country's statistics agency readjusted the calculation system, according to official data showed on Friday.

New home prices climbed in January from a year earlier in 68 of the 70 major cities tracked by the National Bureau of Statistics (NBS), with 10 of them registering double-digit growth.

Prices rose 6.8 percent from a year earlier in Beijing and 1.5 percent in Shanghai, the agency said. Excluding government-subsidised housing, prices were up an annual 9.1 percent and 1.8 percent in those two cities, respectively.

The report marked the launch of a new data set by the statistics agency, so changes were not directly comparable with previous months.

China scrapped a nationwide property index and refined its reporting methods for individual cities, which economists said should improve the reliability of the data.

"We will have to wait several months more to examine the quality of the data," said Cheng Dong, an analyst with BOC International in Shanghai.

China has been trying to rein in runaway property price rises since late 2009. It unveiled a new round of tightening in January, raising mandatory down payments and limiting multiple home purchases.

Yet new home prices continued to rise in 60 cities in January from December. They were level in seven cities and declined in three cities, the NBS said.

Prices rose 0.8 percent month on month in Beijing and 0.9 percent in Shanghai, the agency said. Excluding government-subsidised housing, they were up 1.0 percent and 1.1 percent, respectively, in the two cities.

Subsidised dwellings account for a small proportion of the overall property supply in China, but the government is ramping up its investment in public housing as part of efforts to cool the market. It plans to build 10 million affordable units this year, up from last year's target of 5.8 million.