A 401(k) plan is the common name in the United States for the defined-contribution pension account defined in the Internal Revenue Code. Under the plan, retirement savings contributions are provided (and sometimes proportionately matched) by an employer, deducted from the employee's paycheck before taxation (therefore tax-deferred until withdrawn during retirement), and limited to a maximum pre-tax annual contribution that is subject to change over time.

Various papers use this data from different sources for varying purposes. As an example please refer to Agnew et. al. (2003) provided as a link under 'Documentation': This proprietary dataset was collected by Agnew et al. (2003). It originates from data on a 401(k) plan provided by Citistreet (formerly State Street Global Advisors). The data includes information on 6,778 participants for the time period April 1994–August 1998. It contains demographic characteristics and investment choices.

Research

$100 bills on the sidewalk: Violations of no-arbitrage in 401(k) accounts
Choi et. al. (2011)
Review of Economics and Statistics
Reinforcement learning and savings behaviour
Choi et. al. (2009)
Journal of Finance
Mental accounting in portfolio choice: Evidence from a flypaper effect
Choi et. al. (2009)
American Economic Review
Portfolio choice and trading in a large 401(k) plan
Agnew et al. (2003)
American Economic Review
The Power of Suggestion: Inertia in 401(k) Participation and Savings Behavior
Madrian and Shea (2001)
Quarterly Journal of Economics