 CHICAGO, June 15, 2021 PRNewswire -- Morningstar, Inc. Nasdaq: MORN, a leading provider of independent investment research, today reported estimated U.S. mutual fund and exchange-traded fund ETF flows for May 2021. Long-term mutual funds and ETFs collected 83 billion during May, materially less than their 156 billion haul in March and 124 billion intake in April. 