The iShares National Muni Bond ETF (NYSEARCA: MUB ) offers broad exposure to the municipal bond market in the United States. It’s the second largest fund in the category , with around $39 billion in assets. Nearly 100% of the portfolio is investment-grade. Diversified andJoseph Jones is a professor at The University of Southern Mississippi. He focuses on portfolio construction from a dividend growth investment perspective. The insights expressed in his research are solely his own; they may not represent the ...