NEW YORK--(BUSINESS WIRE)--Exchange-traded funds (ETFs) are increasingly being used as favored vehicles to express changing views on the high-yield market, according to Fitch Ratings. The increase is likely reflective of more limited liquidity in the underlying high-yield bond markets, as well as the growing importance of liquid investments at a time when views on the future path of interest rates and macro fundamentals are shifting continuously. High-yield ETF investors have historically sough