To pursue its goal, the fund invests in investment grade, short-term, U.S. dollar denominated debt securities issued by U.S. and foreign issuers, such as commercial paper, including asset-backed commercial paper, promissory notes, certificates of deposit and time deposits, variable- and floating-rate debt securities, corporate bonds, municipal bonds, bank notes and bankers acceptances, repurchase agreements, obligations that are issued by the U.S. government, its agencies or instrumentalities, including obligations that are not guaranteed by the U.S. Treasury, such as those issued by the Federal National Mortgage Association (Fannie Mae) and the Federal Home Loan Mortgage Corporation (Freddie Mac) (U.S. government securities). The fund is an actively managed exchange-traded fund and therefore does not seek to replicate the performance of any specific index. The fund may have a higher degree of portfolio turnover than funds that seek to replicate the performance of an index.