How Inflation Affects Cash Deposits: Purchasing Power, Real Rates and Money Planning

Inflation affects cash deposits through what your money can buy. When prices rise, cash earning no interest loses purchasing power. A bank deposit earns interest, but whether it keeps up with prices depends on its return, inflation over the same period, and applicable taxes and fees. Even when your account balance increases, the purchasing power behind it may have declined.

Paying rent, preparing for next semester’s tuition and covering unexpected medical expenses all require accessible money with a clear purpose, so deposits still have a necessary role. Understanding inflation helps you find a suitable way to allocate money for different needs.

If you are also learning about investing, starting small can help you understand the process while keeping money for living costs and emergencies separate.

How inflation affects cash: balance versus purchasing power

Inflation is an increase in the general price level. Suppose a basket of goods that costs NT$100 today costs NT$103 a year later. The price of that basket has increased by 3%. Your NT$100 has not been deducted from your wallet, but it no longer buys the same basket.

Whether your principal has decreased and whether your purchasing power has decreased are therefore different questions. The first concerns the amount of money you hold; the second compares that amount with prices. Both matter when evaluating money you intend to keep for a long time.

A price increase in one item does not necessarily establish broad inflation. A typhoon might temporarily raise some vegetable prices without causing every other good and service to rise at the same rate. To understand the specific causes of inflation, see what inflation means and what causes it. This article focuses on its relationship with cash and savings.

Understand CPI and core CPI before comparing rates

CPI measures average price changes, not your individual bills

The Consumer Price Index, or CPI, tracks average changes in the prices of consumer goods and services purchased by households. Its categories are weighted to reflect consumption patterns; it is not a simple average of every product’s percentage price change.

A year-on-year CPI rate compares a month with the same month a year earlier. A month-on-month rate compares consecutive months. An annual-average rate compares the average index across two years. Match your inflation measure to your investment period: a single monthly change is not an annual inflation rate.

For example, if CPI was 100 a year ago and is 103 a year later, the price increase over that period is 103 ÷ 100 − 1, or 3%. Comparing the index at the beginning and end of a holding period can also help measure changes in purchasing power.

Your own experience may differ from CPI. Households that spend more on eating out, rent, driving or care services have different spending weights and may feel different financial pressures. CPI provides a shared benchmark, while a personal budget should be reviewed and assessed against your own spending patterns. DGBAS price-statistics FAQs

Taiwan’s core CPI excludes fresh fruit, vegetables and energy

Taiwan’s core CPI excludes fresh fruit and vegetables and energy from the headline index. This reduces the influence of some short-term disturbances, such as weather and energy-price fluctuations, when examining underlying price trends. Excluded items may differ across countries, so their CPI measures may not be suitable for direct comparison.

Core CPI does not mean that those expenses are unimportant. Households still buy groceries and pay for electricity and fuel. Headline and core CPI provide complementary information: one describes overall average price changes, while the other helps examine trends after excluding selected volatile components. DGBAS statistical tables

Why can a deposit earn interest but lose purchasing power?

Nominal interest versus real interest

A nominal interest rate is the rate agreed for the deposit. A real interest rate takes inflation into account. A commonly used approximation is:

Approximate real interest rate = nominal interest rate − inflation rate

At relatively low rates, this makes the direction easy to understand. A more precise purchasing-power return over the same period is:

Real return = (1 + nominal return) ÷ (1 + inflation rate) − 1

Where taxes or fees apply, reflect them in the return actually received. Using an assumed future inflation rate produces a scenario estimate; using realized inflation after the period ends produces a backward-looking measure. ECB explanation of nominal and real interest rates

A one-year example with NT$1 million

Assume a principal of NT$1 million, a 2% annual interest rate and 3% inflation over the same year, with no taxes or fees. These are illustrative assumptions, not current bank quotations or an inflation forecast for Taiwan.

The account gains NT$20,000, but its purchasing power falls by approximately NT$9,709 when measured at the original price level.

Different inflation scenarios produce different results

With the same assumed 2% annual interest rate, deposits do not inevitably lose purchasing power:

If inflation falls from 5% to 3%, prices are rising more slowly; they have not automatically returned to their earlier level. A sustained decline in the general price level is deflation. Cash earning no interest may gain purchasing power in that setting, although changes in income, employment and spending needs still matter.

Inflation compounds over time

Multiplying an annual inflation rate by the number of years does not precisely measure cumulative inflation. Each year’s price increase applies to the previous year’s already-adjusted price level.

For cash earning no interest and a constant annual inflation rate:

Future cash expressed in today’s purchasing power = cash amount ÷ (1 + annual inflation rate)^years

If deposit interest is reinvested annually and both the interest rate and inflation rate remain constant, purchasing power can be estimated as principal × [(1 + annual interest rate) ÷ (1 + annual inflation rate)]^years. If actual interest rates and prices change each year, calculate the result year by year.

The calculation also works in reverse. A set of expenses costing NT$5 million today would cost approximately NT$9.03 million in 20 years under an assumed 3% annual inflation rate. This illustrates why a long-term savings target should be revisited, rather than judging progress only against an amount set many years ago.

Cash, demand deposits and time deposits still serve different purposes

Purchasing power matters, but money also needs to pay bills, cover emergencies and remain available for planned expenses. Choosing solely by return can overlook restrictions that matter when you need the funds.

For tuition due in six months, compare the payment deadline with the maturity date before choosing a time deposit. For emergencies that can occur without notice, keep a sufficient portion readily accessible. Splitting money among deposits with different maturities may help cash management, but does not eliminate inflation risk.

The size of an emergency fund depends on necessary expenses, income stability and family responsibilities. See how much emergency savings to keep and where to hold them.

Organize money around its purpose

Layer one: everyday expenses and emergencies

List essential spending such as rent, food, transport, debt payments and care costs, and retain accessible funds. This portion helps keep daily life running and reduces the chance of having to sell investments unexpectedly to meet an urgent bill.

Layer two: money with a known near-term use

For tuition, insurance premiums, renovations or other planned expenses, compare the date and amount required with the financial product’s maturity. If the bill must be paid in New Taiwan dollars, converting all the money to foreign currency or stablecoins introduces exchange-rate and conversion-cost variables.

Layer three: longer-term money that can tolerate volatility

After covering the first two layers, consider whether other investments suit the remaining funds. Compare expected returns with potential losses, fees, liquidity and concentration. A higher advertised rate alone is not a reason to assign a fixed, large share of your assets to a product.

Diversification reduces reliance on a single asset, but cannot guarantee a profit or an inflation-beating result. Explore ways to diversify and how to assess risk tolerance. Revisit your budget, income and financial goals periodically so that your plan reflects current needs.

An additional tool to understand: ZONE Wallet Easy Earn

If you have already arranged money for living costs and emergencies and understand virtual-asset risks, you can explore ZONE Wallet Easy Earn. It is a 28-day investment product with an expected annualized return of 4.8%, offering a new-generation way to put short-term funds to work.

Frequently asked questions about inflation and deposits

Should I withdraw all my savings if deposit interest is below inflation?

That comparison alone is not enough to decide. Holding the proceeds as non-interest-bearing cash does not remove inflation’s effect, while investing creates different risks. Start with the purpose and expected use date of your money.

Does lower core CPI mean my living costs are lower?

No. Headline and core CPI cover different items, and you still pay for some expenses excluded from core CPI. Your financial pressure also depends on spending patterns and income changes.

If the central bank raises rates, will my deposit beat inflation?

Not necessarily. The policy rate is not the rate offered by every bank or deposit product. Even if your deposit rate rises, compare it with inflation over the same period and account for taxes and fees.

Does holding dollars or stablecoins remove Taiwan’s inflation risk?

No. If your expenses are paid in New Taiwan dollars, the exchange rate and conversion costs still affect the outcome. Stablecoins also carry risks associated with their mechanisms and trading. Dollar denomination does not guarantee real purchasing power.

Is any investment certain to beat inflation?

Ordinary investment products should not be treated as certain to preserve purchasing power in every period. An asset that may outperform inflation over a long horizon can still decline over a shorter period. Your entry price, holding period, costs and withdrawal needs all affect the result.

Manage inflation while keeping savings fit for their purpose

Three steps can help: use CPI and your everyday spending to understand prices, use real interest rates to evaluate deposit returns, and allocate cash, deposits and other investments according to purpose and timing.

Preserve the flexibility your daily life requires and update your long-term goals regularly so that your financial arrangements keep up with your actual needs.

What is ZONE Wallet?

ZONE Wallet is a Taiwan-based virtual asset exchange offering crypto purchases and sales in New Taiwan dollars and dollar-cost averaging transactions. Users can review the transaction process, fees and risks before deciding whether to use its services.

ZONE Wallet also offers corporate accounts for businesses to assess against their payment and asset-management needs. Individual and corporate users should read the applicable terms and understand each service’s scope and limitations.

Disclaimer: This article is for education and information and does not constitute investment or tax advice. Interest rates, inflation rates and purchasing-power calculations are explicitly identified as assumptions and do not represent future outcomes. Virtual assets involve price volatility, liquidity constraints and other investment risks. Assess your finances and capacity for loss and read the applicable product terms before investing.