How to Use Excel to Calculate the ROI on a Product. "Return on investment" is a financial calculation used to gauge how well the money you invest earns you even more money.

Calculating the return One of the best methods for calculating an average return for a stock investment is the XIRR function in Excel.

Knowing how to calculate your portfolio's returns is essential to becoming a savvier investor. Learn the basic principles here to correctly calculate your investment portfolio returns.

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