How much value does cash lose to inflation?
At about 3% inflation a year, close to the long-run average, money loses roughly half its purchasing power over two decades. That sealed $10,000 still reads $10,000, but it spends like $5,537. Nobody robbed you; robbery would have been faster. Inflation just quietly ate the value and left no note.
What beats inflation?
You can't stop inflation, but you can outgrow it. Money that's invested tends to grow faster than prices rise, so its real buying power climbs instead of sinks. The same $10,000 invested at around 7% would grow to about $21,426 in real terms over 20 years: more than double, while the cash version shrank by half. That gap is the entire reason to invest rather than hoard.
So is holding cash always bad?
No. A sensible cushion of cash, your emergency fund, is exactly right, because its job is to be there instantly, not to grow. The leak is piling extra cash far beyond that and calling it safe. Money meant to grow has to be invested just to keep pace with prices, let alone get ahead.
Guess first
$100 of groceries, thirty years on.
Prices rise 2.5% a year for thirty years. What do today’s $100 of groceries cost then?
$100 × 1.02530 = $209.76. Same cart, same shop: smaller dollar.
Nothing on the shelf got better. The unit you measure with shrank. All eight in Guess first
Questions
Frequently asked
Does money in a savings account lose value?
If the account's interest rate is below the inflation rate, yes, in real terms your money is slowly losing buying power even as the balance ticks up. Over decades that erosion compounds into roughly half.
What is a good inflation rate to assume?
Around 2–3% a year is a reasonable long-run planning assumption for the US, though it varies year to year. The exact number matters less than the direction: prices drift up, idle cash drifts down.
