The study looked at how much control central banks have over the amount of money in circulation in Sri Lanka. They used two methods to investigate this: the traditional money multiplier approach and the idea that money supply is determined by the financial system itself. The results showed that the money multiplier is not stable, which means that the amount of money in the economy is not easily controlled by the central bank. This suggests that factors beyond the central bank's control, like bank lending, play a significant role in determining the money supply.