Wikipedia describes compound interest as:
Compound interest
arises when interest is added to the principal of a deposit or loan, so that,
from that moment on, the interest that has been added also earns interest.
This addition of
interest to the principal is called compounding.
A bank account, for example, may have its interest compounded every year: in this case, an account
with $1000 initial principal and 20% interest per year would have a balance of
$1200 at the end of the first year, $1440 at the end of the second year, and so
on.
And it was Albert
Einstein said:
"Compound
interest is the eighth wonder of the world.
He who understands
it earns it... he who doesn't... pays it."
Let's look at some
numbers so we can see compound growth in action.
If I were to ask
you which option you'd prefer, how would you (honestly) answer:
1. 1p that doubles
every day for a month
2. £1m cash in your
bank account immediately
Now, you may be
thinking that this is obviously a leading question and you'd be correct! But
I'm guessing if the question was asked out of the blue many would opt for 2.
In fact, option 1
would return in excess of £10m!
The power of
compound interest at work.
I'll admit that
it's unreasonable to expect a 100% return on any investment every single day,
however, it's the principle that I want to concentrate on.
In effect, all
interest earned on any investment is effectively free money and interest earned
on interest is the holy grail.
The 3 Rules
The amount of money
you'll get back on any investment is determined by:
1. The amount you
invest
2. The length of
time your money is invested for
3. The rate your
money grows at
Back to some
numbers.
Let's say you have
a target of £300,000 at age 60.
Age
Years to 60 Growth Rate
Monthly Payment Total Invested
30
30
5%
£366 £131,760
40
20
5% £736
£176,640
50
10
5% £1,936 £232,320
So as you can see,
the longer you leave it the more it'll cost over the long term.
Looking at another example, let's say you invested £366 per month between the ages of 30 and
40 but then stopped.
Here's how the
numbers look:
Age.......................30..............40..........50
Years to
60............30..............20..........10
Growth
Rate..........5%.............5%..........5%
Monthly
Payment...£366..........£369........£971
Total
Invested.......£43,920.....£88,560.....£116,520
Maturity
Amount...£150,513....£150,513....£150,513
As you can see, the
'cost of delay' is stark, so if you can afford to invest more
at an earlier age you'll save a hefty sum, all factors being equal.
So, time indeed can
be your friend when investing.
Looking at rule 3,
how do the numbers look if the return is 7% pa? (remember, the target is
£300,000)
Age.......................30..............40...........50
Years to
60............30..............20...........10
Growth
Rate..........7%.............7%..........7%
Monthly
Payment...£255..........£588........£1744
Total
Invested.......£91,800.....£141,120...£209,280
As you can see,
there's not a huge saving if you start investing at 50 (10%), however, it's a
different story at age 30 where you'd save 30%!
And what about the
cost of delay example at 7% pa where you invest the £255 per month between the
ages of 30 and 40 but then stop?
Age.......................30..............40...........50
Years to 60............30..............20...........10
Growth
Rate..........7%.............7%..........7%
Monthly
Payment...£255...........£333........£987
Total
Invested.......£30,600......£79,920....£118,440
Maturity
Amount...£169,738.....£169,738..£169,738
You get the point,
I'm sure.
Whilst there are a
number of factors you should take into account before you invest, some of the
key ones are (in no particular order):
- Inflation
- Investment fees
- Transaction fees
- Adviser fees (if
you use one)
- Product fees
- Tax
Key Considerations
It's not always
easy to invest the amounts you want when you have other commitments, however by
budgeting and being more aware of where you're spending your money it's
possible to find additional sums each month.
Action Point
If you do want
to analyse where your money goes each month, the tool we recommend is You Need
A Budget.
After all, if
you're able to invest another £100-£200 each month you'll be able to
(potentially) enjoy the benefits of the 8th wonder of the world!
Ray Prince is a fee-based Certified Financial Planner with Rutherford Wilkinson Ltd and helps UK
Resident Doctors and Dentists plan to achieve their financial objectives. Just
visit http://www.medicaldentalfs.com where you can request your free
retirement planning guide.
Rutherford
Wilkinson ltd is authorised and regulated by the Financial Conduct Authority.
Credit: Ray Prince
