Your Portfolio Tracker Is Answering a Question You Never Asked

Your portfolio tracker appears to provide a single, precise figure indicating the amount of money earned from investing over a specific period. However, upon closer examination, it becomes clear that this figure may not accurately reflect the various elements contributing to your portfolio's growth.

The tracker does not break down the sources of growth, such as dividends, contributions, market performance, fees, or the timing of transactions. These factors can significantly impact the overall return, sometimes by thousands of dollars. Without a clear breakdown, it is difficult to determine whether the growth is primarily due to your investment decisions, contributions, or market movements.

The author, a self-taught engineer with a goal of financial independence, discovered that no single portfolio tracker can answer the specific question of whether their portfolio is still on track despite contributing less than usual. The tracker's underlying model treats deposits as mere bookkeeping events, failing to capture the history of how the portfolio evolved over time. This approach discards valuable information about the portfolio's trajectory and the impact of various events on its growth.

To gain a more comprehensive understanding of their portfolio's performance, the author had to build their own tracker. They identified four distinct types of returns: unrealized gain, realized gain, time-weighted return, and money-weighted return. Each of these metrics provides different insights into the portfolio's performance, and relying on a single "return" figure can be misleading.

In summary, the portfolio tracker's single, precise figure fails to answer critical questions about the portfolio's growth, leading to potential misunderstandings about the effectiveness of one's investment strategy.