There are three broad investment categories for mutual funds (equity, bond, and money market - in declining order of historical returns). That is an oversimplification but adequate to explain the effect of expenses. In an equity fund where the historical gross return might be 10%, a 1% expense ratio will consume approximately 10% of the investor's return. In a bond fund where the historical gross return might be 8%, a 1% expense ratio will consume approximately 12.5% of the investor's return. In a money market fund where the historical gross return might be 5%, a 1% expense ratio will consume approximately 20% of the investor's historical total return. Thus, an investor must consider a fund's expense ratio as it relates to the type of investments a fund will hold.