SHANGHAI, Jan 15 (Reuters) - China’s central bank on Friday rolled over maturing medium-term loans while keeping the interest rate unchanged for an ninth straight month. The People’s Bank of China (PBOC) said in a statement it was keeping the rate on 500 billion yuan ($77.24 billion) worth of one-year medium-term lending facility (MLF) loans to financial institutions steady at 2.95% from previous operations. ($1 = 6.4736 Chinese yuan)