New home prices in China rose at their fastest pace in five months in May, complicating government efforts to keep frothy housing markets under control as it rolls out more stimulus for the slowing economy.

Average new home prices in China’s 70 major cities rose 0.7% in May from the previous month, picking up from a 0.6% rise in April and the quickest pace since December, according to National Bureau of Statistics (NBS) data.

That marked the 49th straight month of price gains. Sixty-seven of the total 70 cities surveyed by the NBS reported higher prices in May, the same as April.

On an annual basis, home prices increased 10.7% in May, unchanged from April’s growth rate.

Higher prices were mainly driven by the smaller tier-3 cities, up 0.8% on a monthly basis compared with a 0.5% gain in April, the statistics bureau said in a note accompanying the data.

Prices in China’s four top-tier cities - Beijing, Shanghai, Guangzhou and Shenzhen - saw slower growth in May, increasing 0.3% versus 0.6% growth in the previous month.