The Vanguard Total Bond market ETF (NYSE:BND) with total assets under management at $250 billion is the largest fixed-income-based exchange-traded fund in the world. The purpose of BND is to provide passive broad-market exposure to U.S. investment-grade bonds in a low-cost structure. The expense ratio of just 0.04% coupled with a current yield of 2.7% distributed through a monthly dividend makes BND a good choice for most investors to balance a portfolio against higher-risk equity exposure. In general, if interest rates fall, bonds should appreciate and that was the case in 2019 when