In a defined contribution plan, the amount of money contributed is defined, but the eventual benefits received by the employee depend on the contributions made and the returns earned on those contributions over time. Common examples include 401(k) plans in the United States, where employees can choose how much to contribute, and often receive matching contributions from their employer. The funds are invested in various investment vehicles such as stocks, bonds, or mutual funds, and the account balance at the time of retirement will determine the retirement income.