What inflation means in practice
Inflation is a general rise in prices over time. The practical effect is that each dollar buys slightly less than it did the year before. At 3% annual inflation, something costing $100 today would cost roughly $134 in ten years and $181 in twenty.
It directly affects the real value of savings, the effective cost of a mortgage, superannuation projections, and the burden of indexed debt.
How Australia measures inflation
The Australian Bureau of Statistics (ABS) tracks inflation using the Consumer Price Index (CPI). The CPI measures price changes across a representative basket of goods and services (housing, food, transport, healthcare, education, and other categories) and is published quarterly.
The Reserve Bank of Australia (RBA) targets an inflation rate of 2–3% per year on average over the economic cycle. This is a medium-term objective, not a hard limit for any single year. Interest rate decisions are the RBA's primary tool for influencing where inflation sits.
Real vs nominal returns
A nominal return is the raw percentage gain before adjusting for inflation. A real return shows what was actually gained in purchasing power after accounting for price rises.
If a savings account earns 4% per year and inflation runs at 3%, the real return is approximately 1%. The balance grows in dollar terms, but purchasing power increases only slightly.
More precisely, the real return is: (1 + nominal) / (1 + inflation) − 1. At small numbers, subtracting the inflation rate from the nominal return is a reasonable approximation.
The difference between real and nominal matters most for long-term projections. A superannuation balance projected to reach $1.5 million in 30 years is expressed in future (nominal) dollars. In today's purchasing power at 2.5% average inflation, that same amount is equivalent to roughly $720,000, still significant but considerably less than the headline figure suggests.
Inflation and savings accounts
Cash savings earn interest, but inflation erodes the purchasing power of that cash. In periods where savings rates lag behind inflation, cash holdings lose real value even as the nominal balance grows.
This does not mean cash savings are pointless. Emergency funds and short-term savings serve genuine purposes regardless of real returns. But over long periods, heavy reliance on cash savings alone may not keep pace with the rising cost of living.
Inflation and debt
Inflation affects debt differently from savings. If a mortgage is $500,000 and wages and prices rise with inflation, the real burden of those repayments gradually falls over time, as the same nominal payment represents less purchasing power each year.
Not all debt benefits from inflation this way. HECS-HELP debt is indexed to CPI each year, meaning the balance rises with inflation rather than being eroded by it. In years of elevated inflation, HECS balances can grow substantially. The 7.1% indexation applied in 2023 is a recent example of this effect.
Inflation and superannuation
Super projections (from fund statements, calculators, and financial models) typically show nominal balances at retirement. The real (inflation-adjusted) value depends on how inflation tracks over the intervening years.
A projection of $1.2 million at retirement in 30 years, at 2.5% average inflation, is worth roughly $575,000 in today's purchasing power. Comparing a projected super balance to today's living costs requires accounting for this gap. They are not directly comparable figures.
This is why benchmarks like the ASFA Comfortable Retirement Standard are updated annually. The target rises with inflation to maintain its real-world meaning.
The purchasing power halving time
Using the Rule of 72: divide 72 by the inflation rate to estimate how long it takes for purchasing power to halve. At 3% inflation, purchasing power halves in roughly 24 years. At 2%, it takes about 36 years.
For someone 25 or 30 years from retirement, this is a meaningful number. The retirement income that feels adequate today will need to be considerably higher in nominal terms to buy the same goods and services in the future.
Common misconceptions
"My savings balance is growing, so I'm getting ahead"
Nominal balance growth and real wealth growth are different things. If your balance grows at 3% but inflation is 3%, your purchasing power is unchanged. Growing in nominal terms while standing still in real terms is a common experience during periods where savings rates fail to outpace inflation.
"Inflation is always bad"
Moderate inflation (within the RBA's 2–3% target) is considered economically healthy. It encourages spending and investment rather than hoarding, and gives the RBA room to reduce rates in downturns. Very high or persistently unpredictable inflation is the problem, not moderate and steady price growth.
"My super projection is in today's dollars"
Almost all super projections are in nominal future dollars unless explicitly stated otherwise. The headline projection will look larger than what it can actually buy at retirement. Applying an inflation adjustment gives a better sense of what the projected balance means in terms of today's purchasing power.
Frequently asked questions
How does inflation affect long-term investment returns?
Broad share market investments have historically delivered real returns above inflation over long periods. Nominal returns from equities tend to incorporate inflation expectations through earnings and dividend growth over time. This is why diversified share investments are often discussed as a long-term inflation hedge, though short-term volatility is significant and past performance is not a guarantee.
Should I adjust my savings goal for inflation?
If your savings goal is a fixed amount in today's dollars, yes. A $50,000 emergency fund goal in five years needs to account for the fact that $50,000 will buy less in five years than it does today. Increasing the nominal target by the expected inflation rate each year keeps the real goal intact.
Does the RBA directly control prices?
No. The RBA influences inflation primarily through the cash rate, which affects borrowing costs across the economy. Higher rates slow spending and ease price pressures; lower rates do the opposite. The prices of individual goods and services are set by markets, not the RBA. The RBA manages the broader conditions that influence price levels over time.
What is the difference between CPI and underlying inflation?
The headline CPI captures all price changes including volatile items like food and energy. The RBA also monitors "trimmed mean" inflation, which strips out the most volatile price movements to give a cleaner picture of underlying demand-driven inflation. Both measures are published by the ABS.
Use the Inflation Calculator to see how purchasing power changes over time. To understand how compounding interacts with inflation on long-term investments, see How Compound Interest Builds Wealth Over Time or try the Compound Interest Calculator.