Indian stock-index futures fell after the benchmark gauge plunged the most in 16 months amid a slump in oil prices.

SGX CNX Nifty Index futures for January delivery lost 0.4 percent to 8,110 at 9:48 a.m. in Singapore. The underlying CNX Nifty Index (NIFTY) on the National Stock Exchange of India Ltd. sank 3 percent to 8,127.35 yesterday. The S&P BSE Sensex (SENSEX) tumbled 3.1 percent to 26,987.46. The Bank of New York Mellon India ADR Index of U.S.-traded shares decreased 2.8 percent.

The MSCI Asia Pacific Index (MXAP) slipped 0.3 percent, poised for a third day of losses, as a gauge of global equities slid to the lowest level in three weeks. While the fall in oil to below $ 50 a barrel has cut energy costs for India, which imports about 80 percent of its crude, the rout signals a weak global economy, according to Ambit Investment Advisors Pvt.

“The sharp fall in markets came as a surprise,” Dipen Shah, head of private-client group research at Kotak Securities Ltd., wrote in an e-mail yesterday. “The sustained fall in crude prices is positive from the Indian economy’s point of view, though.”

The Sensex is on course for a second monthly loss after yesterday’s tumble. The gauge retreated 4.2 percent in December, its worst monthly performance since February 2013, as foreign investors pulled $ 116.9 million from local stocks, paring their net inflows for 2014 to $ 16 billion.

Global investors bought a net $ 77.3 million of local shares on Jan. 5, taking total purchases in January to $ 123.2 million. The Sensex is valued at 14.8 times projected 12-month earnings. The MSCI Emerging Markets Index trades at 10.8 times.

To contact the reporter on this story: Rajhkumar K Shaaw in Mumbai at rshaaw@bloomberg.net

To contact the editors responsible for this story: Michael Patterson at mpatterson10@bloomberg.net Phani Varahabhotla, Chan Tien Hin