Bank Indonesia has been the most aggressive central bank in Asia this year, not only on interest rates but on foreign-currency intervention as well. The bank has drained almost 10 percent from foreign reserves this year, the most among Asia\u2019s largest economies, to help bolster the rupiah amid a rout in emerging markets. The Philippines has cut its buffers by almost 5 percent, while reserves in India have fallen more than 2 percent. Malaysia and South Korea have managed to boost their reserves even as their currencies also weakened. The rupiah slumped to its lowest level since the 1997-98 Asian financial crisis last week, while India\u2019s rupee lost about 12 percent against the dollar this year. With volatility likely to remain high, reserves are becoming more important in assessing the buffers of an economy, said Eugenia Victorino, head of Asia strategy at Skandinaviska Enskilda Banken AB in Singapore. \u201cThis is particularly true for India, Indonesia, and the Philippines, countries running current-account deficits and regarded as more exposed to the negative sentiment on emerging markets,\u201d she said. Indonesia\u2019s reserves fell to $117.9 billion in August, the lowest since January 2017, though still enough to finance 6.6 months of imports and servicing of the government\u2019s external debt, according to the central bank.