What this does: it tells you how much a value went up or down, as a percentage of where it started — the same math behind stock returns, price hikes, and growth rates.
Example: you bought a stock at ₹100 and it's now trading at ₹135. Old Value = 100, New Value = 135 → +35% change. The same formula works for salary hikes, rent increases, or a drop in weight.