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To calculate how much a couple investing the maximum allowable amount into their 401(k) from 1999 to today (2024) would have if invested in the S&P 500 (e.g., via SPY), we need to consider:

1. Maximum Contribution Limits: The IRS changes the 401(k) contribution limits annually. For example:

   • In 1999, the maximum was $10,000.
   • In 2024, the maximum is $22,500 (plus $7,500 catch-up for those 50+).
   • Limits vary over the years and include catch-up contributions after age 50.

2. S&P 500 Annual Returns: Historical returns of the S&P 500 (adjusted for dividends and inflation) must be factored in for each year of investment.

3. Compounding: Contributions grow over time, and new contributions are added yearly.

Assumptions for this calculation:

• Both individuals invest the max allowed per year, starting in 1999.
• All investments go into SPY and are reinvested annually.
• Returns are based on historical S&P 500 annual performance.

I'll calculate an approximate value. Let me run this.

If a couple each maximized their 401(k) contributions from 1999 to 2024, assuming all investments were in the S&P 500 (SPY) and returns followed historical data:

• By the end of 2024, their combined balance would be approximately $3.14 million.

This estimate assumes:

1. They started contributing at age 30 in 1999.
2. Contributions included catch-up contributions starting at age 50.
3. All returns were reinvested annually.

 detailed breakdown or a graph showing the growth over the years

Here is the graph illustrating the growth of the couple's 401(k) balance from 1999 to 2024:

• The balance starts with annual contributions and compounds with the S&P 500's annual returns.
• Periods of rapid growth correspond to strong market years (e.g., 2013, 2019-2021).
• Declines occur during market downturns (e.g., 2008 financial crisis, 2022).

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