Inflation
Inflation is the quiet term in every calculation. Leave it out and every long-horizon number is wrong in the same direction.
Inflation is the quiet term in every financial calculation, and leaving it out biases every long-horizon number in the same direction: optimistic. A savings balance that only ever rises looks like progress even while its purchasing power falls, and a goal priced in today's money looks affordable right up until the date arrives.
Two calculations fix most of it. Converting a nominal return into a real one tells you whether an investment is actually gaining ground. Inflating a goal to what it will cost at its date tells you what you are really funding. Neither is difficult, both are routinely skipped, and the second one changes long-horizon targets by multiples rather than by percentages.
These guides state no current inflation rate, because a page that does is describing one month and will be wrong for the rest of its life. The RBI publishes the figures; what is published here is the arithmetic those figures slot into, worked in full so you can redo it with whatever assumption you consider reasonable.
Key terms
- Nominal return
- The return as quoted, before any adjustment for inflation. It is the number on the statement and the number in every advertisement, and on its own it does not say whether you can buy more than you could before.
- Real return
- Return after inflation: (1 + nominal) ÷ (1 + inflation) − 1. The only return that measures a change in purchasing power, and frequently negative on cash held in a savings account.
- Purchasing power
- What a sum of money can actually buy. It falls as prices rise even when the balance is growing, which is why a rising statement balance is not evidence that a saver is ahead.
- Category inflation
- The rate at which a specific category of cost has risen, as distinct from the headline index. Education and healthcare have historically outpaced general consumer inflation in India, which matters for exactly the goals where falling short is least acceptable.
Frequently asked questions
How do I calculate a real return?
Divide one plus the nominal return by one plus inflation, then subtract one. Subtracting inflation from the nominal rate is a good approximation at low rates and increasingly optimistic as rates rise. Do it after tax rather than before, because tax is charged on the nominal gain including the part that only compensated for inflation.
Why does inflation matter so much for long-term goals?
Because it compounds. At 6% a year, costs roughly double in twelve years and triple in twenty. A goal fifteen or twenty years out priced in today's money is therefore under-funded by a multiple rather than by a margin, and the goals with the longest horizons are usually education and retirement — the two it is least acceptable to under-fund.
Is cash always a bad place to keep money?
No — it is a bad investment and a good insurance policy, and confusing the two is the error. Money that must be available within days has one job, and any return it earns is incidental. What is genuinely costly is holding far more cash than that job requires, because the excess is losing purchasing power every year in a way nothing on the statement reveals.
What inflation rate should I assume in planning?
One that suits the category, and then a second one a couple of points away to see how sensitive the answer is. General living costs, education and healthcare do not inflate at the same rate, and using a single assumption across a plan under-provides for two of them. Any single-number answer implies a confidence the assumption does not support.