Indian (SENSEX) stock-index futures swung between gains and losses after the biggest rise in the rupee in 27 years and falling oil prompted a rally in benchmark indexes. The government releases quarterly economic growth data today.

SGX CNX Nifty Index futures for September delivery fell less than 0.1 percent to 5,370 at 10:16 a.m. in Singapore after addind as much as 0.8 percent. The underlying CNX Nifty (NIFTY) Index gained 2.4 percent to 5,409.05 yesterday, the biggest gain since June 28. The S&P BSE Sensex added 2.3 percent, sending its 30-day volatility measure to a 20-month high. The Bank of New York Mellon India ADR Index of U.S.-traded shares increased 0.2 percent. One-month rupee forwards fell 0.2 percent to 67.93 after the rupee surged 3.4 percent to 66.595 yesterday. Brent crude, the benchmark for India, dropped 1.1 percent to $ 113.92 a barrel today.

The Sensex jumped yesterday after a central bank move to sell dollars to state oil importers spurred the rally in the rupee. The gauge has fallen 4.9 percent in August, poised for the biggest monthly loss since February. Stocks have dropped on concerns government efforts to stem a record plunge in the currency may further weaken an economy that grew at a decade-low pace in the year ended March and stoke an unprecedented current-account deficit. Data today may show gross domestic product grew at the slowest quarterly pace in more than four years.

“One silver lining is that the economy’s increasingly sluggish performance will bring some relief in the form of a smaller current-account deficit,” Richard Iley, an economist at BNP Paribas SA, wrote in a note e-mailed yesterday. “As the full extent of India’s growth slowdown is factored in, there is a rising risk that equity outflows re-intensify, continuing to push down the rupee whatever the authorities do.”

Slowing GDP

Indian economic growth slowed to 4.6 percent in the quarter ended June 30, from 4.8 percent in the previous three months, according to the median estimate of 43 analysts in a Bloomberg survey. That would be the slowest pace of expansion since the quarter ended March 2009.

International investors have sold a net $ 788 million of Indian shares in August, extending outflows of $ 986 million in July and $ 1.76 billion in June, according to data from the market regulator. Foreigners have bought a net $ 11.6 billion of the nation’s stocks this year, the second-highest among 10 Asian markets tracked by Bloomberg.

The rupee has depreciated 17 percent in 2013, erasing dollar-based investments by 22 percent from Sensex shares, data compiled by Bloomberg show. The Sensex’s valuation has dropped to 13 times projected 12-month profit, compared with the average of 14 times over the past five years.

The economic slowdown and a weak currency is hurting company earnings. Combined profits for the 30 companies in the Sensex increased 1.4 percent in the three months ended June compared with an estimate of 5.8 percent before the reporting season began, Bank of America Corp. analysts Jyotivardhan Jaipuria and Anand Kumar wrote in a report dated Aug. 19.

To contact the reporter on this story: Santanu Chakraborty in Mumbai at schakrabor11@bloomberg.net

To contact the editor responsible for this story: Michael Patterson at mpatterson10@bloomberg.net