A worker welds at a construction site in Yiliang, Yunnan province, February 28, 2015.[Photo/Agencies]

BEIJING - The Caixin General China Manufacturing Purchasing Managers' Index (PMI), an indicator of manufacturing activity, edged down to 48.2 in December from November's 48.6 percent, a private survey showed Monday.

The reading was the lowest since September, according to the survey conducted by financial information service provider Markit and sponsored by Caixin Media Co Ltd.

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

Operating conditions faced by Chinese goods producers continued to deteriorate in December. Production declined for the seventh time in the past eight months, driven in part by a further fall in total new work, the survey showed.

Data suggested that client demand was weak both at home and abroad, with new export business falling for the first time in three months in December, the survey added.

On Friday, China's National Bureau of Statistics and the China Federation of Logistics and Purchasing released the official manufacturing PMI, which came in at 49.7 in December, up from 49.6 in November.

The official PMI samples 3,000 relatively large enterprises in China. The Caixin PMI samples 420 small- and medium-sized manufacturing enterprises and is relatively volatile due to its small sample size and the dominance of small enterprises.