South Korea's money supply grew at a faster annual pace in September than in the previous month on foreigners' increased portfolio investment and larger bank lending, the central bank said Wednesday. South Korea's M2, a narrow measure of the money supply, rose 4.6 percent to 1,903.2 trillion won (US$1.77 trillion) in September from a year earlier, picking up from a 3.9 percent on-year gain in August, according to the Bank of Korea (BOK).