A tool used to determine the average return on an investment over a period where the amount invested fluctuates, this method accounts for the duration of each investment level. For example, if $1,000 is invested for one year and then another $2,000 is added for six months, the performance isn’t simply the overall gain or loss divided by the total investment. Rather, it reflects the return on each portion of the investment over its specific timeframe, offering a more accurate measure of performance than a simple average.
This calculation method offers a crucial advantage in accurately portraying investment growth amidst dynamic contribution schedules and market volatility. It provides a standardized way to compare investment managers and strategies by normalizing returns, facilitating apples-to-apples comparisons regardless of investment timing or size. Historically, the need for such precision emerged with the rise of modern portfolio management and increasingly complex investment vehicles. This approach ensures that shorter-term fluctuations don’t disproportionately skew the perceived long-term performance.