By Michael S. Derby (Reuters) -Federal Reserve Chair Jerome Powell said on Tuesday the end of the central bank’s long-running effort to shrink the size of its holdings, widely known as quantitative tightening, or QT, may be coming into view. Given the central bank’s long-running goal of leaving enough liquidity in the financial system to allow for firm control of short-term rates and normal money market volatility, Powell said “we may approach that point in coming months, and we are closely monitoring a ...