Rapid demand growth; commodity price volatility; the influence of a broad range of global conditions on wages: all these factors can trigger large changes in relative prices, and this makes the job of capturing underlying inflation harder. So we have to be careful not to focus too narrowly on one particular measure. Instead we need to look at many. And indeed here in the United States we look at a range of different measures of core inflation, for example, that take energy and food prices out of the overall index. We look at these over different time horizons. We look at a variety of other measures that use different statistical techniques to strip out the more volatile parts of the index. These all have limitations, and their relative merits may change over time. Central banks approach this challenge of capturing underlying inflation differently, but ultimately we are all judged by what happens to overall inflation over time. These issues are common to central banks everywhere. But economic and financial integration has brought particular challenges for monetary policy makers in emerging market economies. The broad pattern of exchange rate and monetary policy regimes in emerging market economies has shifted dramatically over the past decade. Most now operate a more flexible exchange rate regime, though a significant number have moved to the opposite extreme, relinquishing monetary sovereignty in favor of full monetary integration.
It is sufficiently larger than the negative investment demand effect from higher interest rates, such that internal balance is attained and monetary policy is able to pursue domestic inflation and growth objectives.4  1  Linda Goldberg, Paolo Pesenti, Joseph Tracy and Matthew Higgins contributed to these remarks. 2  A global financial cycle refers to the global co-movement of credit by banks and capital markets, asset prices, term premia, and risk premia. 3  Fleming (1962) and Mundell (1963). 4  Krugman (1999). The balance sheet effects imparted from a large international debtor position may work against achievement of an improved external balance and attainment of internal balance. BIS central bankers’ speeches  1  Different policy options are available to a country with a high degree of capital mobility and a preference for currency stability. A country may prefer currency stability as an effective nominal anchor, or because of concerns about the broader uncertainties associated with currency volatility. Regardless of the reason and because the exchange rate is not available to absorb external shocks, this country will be in an unfavorable position to achieve domestic macroeconomic objectives by using monetary policy. Instead, monetary policy is aimed at external adjustment. Tighter foreign monetary policy and financial conditions need to be validated by tighter domestic monetary policy to maintain currency stability. With domestic monetary conditions effectively imported from abroad, they may sometimes conflict with domestic growth and inflation objectives. Simply put, currency stability is prioritized. These policy considerations are summarized in the well-known international policy trilemma.