Yemen's financial system is underdeveloped and its economy is largely cash-based. This means that the direct impact of the global financial crisis on the country has been limited. It has, however, also reduced the efficacy of interest-rate adjustments, depriving the Central Bank of Yemen (CBY) of an important monetary policy tool. As a result, the CBY's efforts to manage liquidity will remain primarily focused on the issuance of certificates of deposit and Treasury bills (although the recent issue of a sukuk has increased the options available to the Central Bank). Although the CBY has a stated goal of liberalising interest-rate policy, it will be hindered in this by the vulnerability of the Yemeni riyal (which, having depreciated rapidly until August, has recovered strongly since then). It raised interest rates sharply in the first half of 2010, and they are expected to remain elevated over the forecast period, given high inflation and domestic political instability.