Topic 5: What Can Affect a Budget?

What You Need to Learn

Understand what inflation is and how it is measured using the Consumer Price Index (CPI)
Explain the effect of inflation on individuals and the UK economy
Know how the Bank of England controls inflation
Understand how interest rate changes affect borrowers and savers
Explain how exchange rate changes affect individuals and businesses
Calculate the impact of these factors on a personal budget

5.1 Inflation

Inflation is the general increase in the price of goods and services over time. When inflation occurs, each pound buys less than it did before — this is sometimes described as a fall in the purchasing power of money.

How is inflation measured?

In the UK, inflation is measured using the Consumer Price Index (CPI). The Office for National Statistics (ONS) tracks the price of a "basket" of around 700 goods and services that a typical household buys — from bread and milk to streaming subscriptions and trainers. The basket is updated every year to reflect changing spending habits.

CPI Concept	Explanation
Basket of goods	A representative collection of ~700 items whose prices are tracked each month
Base year	The starting point for comparison (index = 100)
Percentage change	CPI inflation is expressed as a % change over 12 months (e.g. CPI = 3% means prices rose 3% on average)

Rising vs falling inflation

Key distinction: If inflation falls from 5% to 3%, prices are still rising — just more slowly. Prices only fall during deflation (a negative inflation rate).

Term	Meaning	Example
Rising inflation	Prices increasing faster than before	CPI goes from 2% to 4%
Falling inflation	Prices still rising, but more slowly	CPI goes from 4% to 2%
Deflation	Prices actually falling	CPI is -1%

"In real terms"

When we say something has changed "in real terms", we mean after adjusting for inflation. For example, if your wages rise by 2% but inflation is 4%, your wages have fallen in real terms — you can buy less than before even though your pay packet is bigger.

Exam tip: Students often confuse "falling inflation" with "falling prices". Falling inflation means prices are still going up, just at a slower rate. Only deflation means prices actually decrease.

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Quick Check: Inflation Basics

5.1.2 Effect of Inflation on Individuals

Inflation does not affect everyone equally. Some groups are hit harder than others, and in some cases, inflation can actually benefit certain people.

Group	Effect of Inflation	Why?
Pensioners	Suffer most	Many live on fixed incomes (state pension). If prices rise faster than their pension increases, their purchasing power falls significantly.
Savers	Lose out	If inflation is higher than the interest rate on savings, money loses real value over time. A 2% savings rate with 4% inflation means a negative real return.
Workers on fixed wages	Worse off	If pay does not rise in line with inflation, workers can afford fewer goods and services.
Borrowers	Can benefit	The real value of debt falls during inflation. A loan of £10,000 is easier to repay if wages eventually rise with inflation while the debt amount stays fixed.

Real rate of return

Formula: Real rate of return = Interest rate on savings − Inflation rate

Example: Savings account pays 3% interest. Inflation is 5%.
Real rate of return = 3% − 5% = −2%
The saver is losing purchasing power even though their balance is growing.

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True or False: Inflation Effects

5.1.2.2 Effect of Inflation on the UK Economy

High inflation does not just affect individuals — it can damage the whole economy through a chain of negative effects.

Economic Effect	Explanation
Wage-price spiral	Workers demand higher wages to keep up with prices → businesses raise prices to cover wage costs → prices rise further → workers demand even higher wages. A dangerous cycle.
Reduced consumer spending	As everyday goods cost more, consumers cut back on non-essential spending. Businesses see lower sales.
Unemployment	Businesses facing higher costs and lower sales may need to make staff redundant to survive.
Less tax revenue	With fewer people employed and lower spending, the government collects less income tax and VAT, reducing the money available for public services.
Reduced international competitiveness	If UK inflation is higher than in other countries, UK exports become more expensive abroad, hurting trade.

Exam alert: You may be asked to explain the "chain reaction" of inflation on the economy. Remember the sequence: rising prices → less spending → business struggles → job losses → less tax revenue → fewer public services.

5.1.3 Controlling Inflation

The Bank of England is responsible for keeping inflation under control. It does this through the Monetary Policy Committee (MPC), which meets eight times a year to set the Bank base rate (also called the Bank Rate).

Scenario	MPC Action	How It Works
Inflation too high (above 2% target)	Raise interest rates	Borrowing becomes more expensive → people spend less → demand falls → prices stop rising as fast
Inflation too low (below 2% target)	Lower interest rates	Borrowing becomes cheaper → people spend more → demand rises → prices increase to meet target

The 2% target: The UK government sets an inflation target of 2% per year (measured by CPI). The MPC must write a public letter to the Chancellor if inflation moves more than 1% above or below target.

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Fill in the Blanks: Controlling Inflation

5.2 Interest Rates

The Bank base rate (or Bank Rate) is set by the Bank of England's MPC. It influences the interest rates that banks and building societies charge borrowers and pay to savers.

Variable vs fixed rates

Variable Rate	Fixed Rate
Changes when the Bank base rate changes Advantage: Payments can fall if rates drop Disadvantage: Payments can rise unexpectedly if rates increase Best for: People who expect rates to fall or want flexibility	Stays the same for a set period (e.g. 2 or 5 years) Advantage: Certainty — you know exactly what you'll pay each month Disadvantage: You miss out if rates fall; early exit penalties may apply Best for: People who want budgeting certainty

Effect of interest rate changes on borrowers

Worked example: Sarah has a variable-rate mortgage of £200,000. Her monthly payment at 4% is £1,052. If the Bank Rate rises and her mortgage rate increases to 5%, her monthly payment jumps to £1,169 — an extra £117 per month (£1,404 per year). This could seriously affect her budget.

Effect on savers

When interest rates rise, savers benefit because banks pay more interest on deposits. However, if the rate paid on savings is still below inflation, the real return remains negative.

Responsible lending and compounding

Lenders must follow responsible lending rules — they must check that borrowers can afford repayments even if interest rates rise. Compound interest means interest is calculated on both the original amount and any interest already earned (or owed). Over time, compounding can significantly increase both savings growth and debt costs.

Compound interest example: £1,000 saved at 5% compound interest:
Year 1: £1,000 × 1.05 = £1,050
Year 2: £1,050 × 1.05 = £1,102.50
Year 3: £1,102.50 × 1.05 = £1,157.63
After 3 years you have earned £157.63 in interest, not just £150 (which simple interest would give).

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Card Sort: Variable vs Fixed Rates

5.3 Exchange Rates

An exchange rate is the price of one currency in terms of another. For example, £1 = €1.15 means one British pound can buy 1.15 euros.

Sterling strengthening vs weakening

Sterling Strengthens (£ buys more)	Sterling Weakens (£ buys less)
£1 goes from €1.10 to €1.20 Holidays abroad: Cheaper — your pounds go further Property abroad: Cheaper to buy Imports: Cheaper for businesses to buy foreign goods Exports: More expensive for foreign buyers — UK businesses may sell less abroad	£1 goes from €1.20 to €1.10 Holidays abroad: More expensive — your pounds buy less Property abroad: More expensive to buy Imports: More expensive for businesses Exports: Cheaper for foreign buyers — UK businesses may sell more abroad

Memory aid: Strong pound = Shopping abroad is cheaper. Weak pound = Workers (exporters) benefit.

Effect on individuals

Exchange rate changes can directly affect your budget if you:

Go on holiday abroad (your spending money buys more or less)
Buy property overseas (the cost in pounds changes)
Shop online from foreign retailers (prices fluctuate)
Send money to family abroad (remittances become more or less valuable)

Effect on businesses

A strong pound makes imports cheaper (raw materials, stock) but makes it harder to sell exports because UK goods become more expensive for foreign buyers. A weak pound has the opposite effect — exports become more competitive but imports cost more.

Worked example: A UK toy manufacturer exports to the USA. If £1 = $1.20, a toy priced at £10 costs the American buyer $12. If the pound strengthens to £1 = $1.40, the same toy now costs $14 — American customers may switch to cheaper alternatives.

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Quick Check: Exchange Rates

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Flip Cards: Key Terms

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Practice Quiz: External Factors and Budgets

Summary

Key Term	Definition
Inflation	A general rise in the price of goods and services over time
CPI	Consumer Price Index — the main UK measure of inflation based on a basket of ~700 goods
Deflation	A general fall in the price of goods and services (negative inflation)
Real rate of return	Interest rate on savings minus the inflation rate
Bank base rate	The interest rate set by the Bank of England that influences all other rates
MPC	Monetary Policy Committee — sets the Bank base rate, meets 8 times a year
Variable rate	An interest rate that changes when the base rate changes
Fixed rate	An interest rate that stays the same for a set period
Exchange rate	The price of one currency expressed in terms of another
Strengthen / Weaken	A currency strengthens when it buys more foreign currency; weakens when it buys less

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