The tighter spread between junk and high-quality Treasuries reflects the confidence in credit quality of the bonds, which is often put into question during periods of economic stress as witnessed in the recent bout of volatility.

Related: The King of Corporate Bond ETFs

As yields on safer Treasury bonds rise, investors have shifted out of riskier speculative-grade debt and into the relative more attractive safer plays.

Year-to-date, investors have pulled $1.81 billion from HYG. Over 85% of the ETF’s holdings are rated BB or B, but HYG does devote 10% of its portfolio to highly speculative CCC-rated bonds. The fund has a 30-day SEC yield of 5.84% and charges 0.49% per year.

For more information on the fixed-income market, visit our bond ETFs category.