As economic expansion in Indonesia accelerates in line with stronger global growth, BI will tighten monetary policy by raising its main interest rate, the BI rate, from its current level of 6.5%-the lowest level that the rate has reached since its introduction in 2005. Concerns about the effect that interest rate increases will have on capital inflows (given that interest rates in major economies are likely to remain low) have so far deterred the central bank from raising the BI rate, but strong domestic economic growth will make higher interest rates essential in the coming period. In September 2010 BI's board of governors initiated monetary tightening by increasing the commercial banking sector's primary reserve requirement to 8%, from 5% previously. That was followed in December by an announcement that the banking sector's US dollar reserve requirement would be increased to 5% from March 2011 and 8% in June, up from the present level of 1%. Inflation (as measured by the consumer price index) rose above BI's 4-6% target range in November 2010 and again in December. The bank's governors will raise interest rates in the first quarter of 2011. Monetary tightening is then expected to continue during the remainder of the year. The BI rate will average 7.3% in 2011 and 8.4% in 2012-15.