New Delhi, Aug. 21 -- India's private sector economy expanded at the fastest pace since records began in December 2005, according to the HSBC Flash India PMI by S&P Global. The rise in August was powered by a surge in sales volumes and new orders, marking the quickest pace of business activity growth ever recorded.

The HSBC Flash India Composite Output Index, which tracks the combined performance of manufacturing and services, jumped to 65.2 in August from 61.1 in July. This four-point rise signaled a record acceleration in overall private sector business activity. Services outpaced manufacturing, with activity hitting a fresh survey high.

Sub-sector performance reflected broad-based strength. The HSBC Flash India Manufacturing PMI rose...