HYMB's take on the high yield muni space includes some investment grade bonds. By design, the fund reaches further up the credit spectrum, holding about 30% of its portfolio in investment grade securities (20% rated BBB and 10% IG rated A). HYMB holds bonds issued by US states, the District of Columbia, US territories like Puerto Rico and local governments and agencies. Securities included must have at least a year to maturity and are market-value-weighted. Rebalancing occurs monthly. The fund tracked a very similar S&P index prior to Oct, 1 2019.