BEIJING, May 31 -- China's non-manufacturing activity maintained expansion in May, with the purchasing managers' index (PMI) for the sector coming in at 54.5, the National Bureau of Statistics (NBS) said Wednesday.

A reading above 50 indicates expansion, while a reading below 50 reflects contraction.

China's non-manufacturing PMI has remained above 54 this year, indicating a sustained recovery, according to senior NBS statistician Zhao Qinghe.

The sub-index for the service sector was 53.8 in May, higher than the reading of 47.1 a year ago. In particular, the business activities sub-indexes of transport, accommodation and catering stood well above 55 as traveling and offline consumption picked up during the May Day holiday.

The construction sector maintained brisk growth this month with its sub-index for business activities standing at 58.2, Zhao noted. The sub-index measuring expectations for activities in the sector came in at 62.1, revealing strong optimism among construction enterprises.

Wednesday's data also showed that the PMI for China's manufacturing sector came in at 48.8 in May, down from 49.2 in April.