What Is Inflation and How It Quietly Erodes Your Investment Returns
Inflation quietly erodes purchasing power, even at moderate rates. Here's exactly how it works, and why it should shape your investments.
The short version: inflation is the rate at which prices rise over time, quietly reducing what your money can buy. Even moderate inflation compounds into a significant loss of purchasing power over decades. Here’s exactly how it erodes your investment returns.
What inflation actually is
Inflation measures how much the average price of goods and services rises over a period, usually a year. In India, it’s tracked mainly through the Consumer Price Index, or CPI.
A 6% inflation rate means, roughly, that things costing ₹100 today will cost about ₹106 a year from now. It sounds small in any single year. Compounded over decades, it isn’t.
The silent erosion of purchasing power
At 6% annual inflation, prices roughly double every 12 years. That means ₹100 today buys what ₹200 will buy in 12 years, for the exact same goods and services.
This is why holding cash for long periods is quietly costly. Even money sitting safely in a savings account loses real value if its interest rate doesn’t outpace inflation.
Real returns vs nominal returns
Nominal return is the percentage gain you see on a statement, before adjusting for inflation. Real return subtracts inflation from that figure, showing your actual increase in purchasing power.
A fixed deposit paying 6% interest, during a year with 6% inflation, has a real return of roughly zero. You haven’t actually gained any purchasing power, despite the account balance growing.
Why this matters for asset selection
Assets that only preserve your nominal capital, without growing faster than inflation, quietly lose you money in real terms over time. This is a key reason many long-term investors favour equities over cash.
Equities represent ownership in businesses that can raise prices along with inflation, and grow earnings over time. Historically, this has helped equities outpace inflation more reliably than cash or low-yield fixed income.
How to actually plan around inflation
When setting long-term financial goals, always think in today’s purchasing power, then adjust upward for expected inflation over your timeline. A goal set purely in today’s rupee terms will fall short later.
Retirement planning is especially sensitive to this. A retirement corpus that looks generous today can feel meaningfully smaller decades from now, purely due to inflation’s compounding effect.
| Inflation rate | Years for prices to roughly double |
|---|---|
| 3% | ~24 years |
| 6% | ~12 years |
| 9% | ~8 years |
Related reading
- India’s GDP Growth Explained: How It’s Measured and Why It Matters
- RBI’s Repo Rate Decision and Its Impact on Markets
Frequently asked questions
How is inflation measured in India?
Inflation in India is tracked mainly through the Consumer Price Index, or CPI, which measures the average price change of a fixed basket of goods and services.
What’s the difference between nominal and real returns?
Nominal return is your raw percentage gain before adjusting for inflation, while real return subtracts inflation to show your actual gain in purchasing power.
Why does holding a lot of cash long-term lose value?
Cash typically earns little to no interest, so its purchasing power steadily erodes as prices rise through ongoing inflation.
Do equities always beat inflation?
Not in every single year, but historically, equities have outpaced inflation more reliably over long periods than cash or low-yield fixed income.
How should inflation affect my retirement planning?
You should estimate your retirement corpus in future purchasing power terms, not today’s rupee value, since inflation compounds significantly over decades.