Vanguard Total Stock Market Index Fund (VTSAX)

The fund employs an indexing investment approach designed to track the performance of the index, which represents approximately 100% of the investable U.S. stock market and includes large-, mid-, small-, and micro-cap stocks. It invests by sampling the index, meaning that it holds a broadly diversified collection of securities that, in the aggregate, approximates the full index in terms of key characteristics.