In less than two months, Turkey will mark the first anniversary of the start of an unusual monetary policy experiment, and it may well do so by calling it off. The experiment hinged on cutting interest rates while raising banks’ reserve ratio requirements, and as recently as August, the central bank was hoping it would be able to slow a local credit boom a bit but still protect exports by keeping the currency cheap. Instead, an investor exodus from emerging markets has put the lira to the sword, fuelling at one point a 20 percent collapse in its value against the dollar. That has forced the central bank to roll back some of the reserve ratio hikes and last week it jacked up overnight lending rates in an attempt to boost the currency. It has also sold vast quantities of dollars and is promising to unveil more measures on Wednesday.