Calculating Value of Investments

Calculating value of investments

  • Investments change value over a number of years.
  • Appreciation is the increase in value of an item. A common example of this is house prices. Each year, the value of a house increases, so we say that its value appreciates. The rate of appreciation is often given as a percentage.
  • Depreciation is the decrease in value of an item. A common example of this is car prices. Each year, the value of a car decreases, so we say that its value depreciates. The rate of depreciation is often given as a percentage.

How to work out appreciation and depreciation

Compound Appreciation p.a. (a):  FV = P (1 + a/100)n

Compound Depreciation p.a. (d):  FV = P (1 – d/100)n

Formula Key:

FV:    Future value

P:     Principal

n:     number of years

a:     appreciation (% increase)

d:     depreciation (% decrease

  • In order to use these formulae, numbers must be inputted in the correct order.
  • The mnemonic BIDMAS is a helpful way of remembering the order of operations (brackets, indices(powers), divide, multiply, add, subtract)

EXAMPLE: I have a stocks and shares NISA which increases in value by 20% each year.  I originally put in £500, so how much will I have in my account in 5 years’ time? 

Compound appreciation: 

FV=P (1 + a/100)n

FV= £500 x (1 + 20/100)

FV= £500 x (1.2)5

FV= £500 x 2.49 (round to 2 decimal places as currency)

FV= £1,245