The seasonally adjusted S&P Global Singapore Purchasing Managers' Index (PMI) was 56.6 in September, marking a continued improvement in private business conditions for 19 straight months, the S&P Global said Thursday.

It added that the growth rate eased to a three-month low but remained marked, Xinhua news agency reported.

The accumulation rate was the most pronounced in eight months, partly due to supply constraints. Inventory levels also declined amid a worsening of supply delays.

Input prices continued climbing last month as firms reported higher raw materials, transport, and labour costs, but at a moderate pace from August.

Though easing from an over three-year peak in August, the confidence levels among Singaporean private sector firms remained above the long-run average and reflected hopes for better business activities.

A PMI reading of 50 and above indicates expansion, while a reading below 50 indicates contraction.