Core Insights - The iShares National Muni Bond ETF (MUB) and the iShares Core US Aggregate Bond ETF (AGG) serve different investment strategies, with MUB focusing on U.S. municipal bonds and AGG covering a broader range of U.S. investment-grade bonds [1][2] Cost & Size Comparison - MUB has an expense ratio of 0.05% and an AUM of $42.0 billion, while AGG has a lower expense ratio of 0.03% and a significantly larger AUM of $136.5 billion [3][9] - The 1-year return for MUB is 1.9%, compared to AGG's 4.4%, indicating a higher yield from AGG [3] Performance & Risk Metrics - Over the past five years, MUB experienced a maximum drawdown of -11.88%, while AGG had a larger drawdown of -17.83% [5] - The growth of $1,000 invested over five years would result in $922 for MUB and $857 for AGG, showing MUB's relative stability [5] Investment Implications - AGG offers a yield of 3.9% that is fully taxable, while MUB provides a lower yield of 3.1% that is exempt from federal taxes, making MUB potentially more attractive for high earners in taxable accounts [9][10] - Investors in lower tax brackets or those using retirement accounts may prefer AGG for its higher taxable yield and broader diversification [10]