Many of the largest ETFs have swelled in size this year as more advisors and investors embrace ETFs. The Vanguard S&P 500 ETF (VOO A) led the pack with $61 billion of new money. This is already a new industry calendar year record if it holds. However, U.S. core equity peers like the iShares Core S&P 500 ETF (IVV A), the SPDR Portfolio S&P 500 ETF (SPLG A), and the Vanguard Total Stock Market ETF (VTI A) are also having a strong year.  Meanwhile, low-cost, broad market fixed income ETFs like the iShares Core U.S. Aggregate Bond ETF (AGG A) and the Vanguard Total Bond Market ETF (BND A) added $14 billion and $8.7 billion, respectively. These and other fixed income ETFs have become key building blocks for portfolios. Low-cost index funds are also a gateway for ETF usage to support other investment styles.