What is ROI?

Return on Investment (ROI) is a performance measure used to evaluate the efficiency or profitability of an investment. It compares the gain from an investment relative to its cost.
Formulas

ROI = ((Final Value - Initial Investment) / Initial Investment) × 100

Annualised ROI = ((1 + ROI)^1/Years - 1) × 100

Net Gain/Loss = Final Value - Initial Investment
Limitations of ROI
Doesn't account for the time value of money

Doesn't consider risk or inflation

Can be manipulated depending on how costs are defined

Should be used alongside other metrics for complete analysis