A survey says Chinese manufacturing ebbed in January to its lowest in more than three years.

It's the latest sign of weakness for the world's No. 2 economy after it posted its slowest annual growth in a quarter century.

An official survey of factory purchasing managers released Monday fell to 49.4 last month.

The latest reading is lower than December's 49.7 on a 100-point scale on which numbers below 50 indicate contraction.

Separately, the private Caixin/Markit purchasing managers' index also showed factory activity continued to shrink.

Meanwhile, activity in China's service industries also eased off. An official purchasing mangers' index for services slipped to 53.5 in January from 54.4 the month before.