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# RULES OF 72

sekiranya anda konsisten 12% return setahun, dalam masa 48 tahun akan menjadi seperti diatas.

Sekiranya konsisten 12% setiap bulan...hanya dalm 48 bulan.

## Rule Of 72

What is the 'Rule Of 72'

rate of return

Years required to double investment = 72 ÷ compound annual interest rate

Note that a compound annual return of 8% is plugged into this equation as 8, not 0.08, giving a result of 9 years

BREAKING DOWN 'Rule Of 72'

compound interest

T = ln(2)/ln(1.08)=9.006

Most people cannot do logarithmic functions in their heads, but they can do 72 ÷ 8 and get almost the same result. Conveniently, 72 is divisible by 2, 3, 4, 6, 8, 9, and 12, making the calculation even simpler.

inflation

The rule of 72 is reasonably accurate for interest rates between 6% and 10%. When dealing with rates outside this range, the rule can be adjusted by adding or subtracting 1 from 72 for every 3 points the interest rate diverges from 8%. So for 11% annual compounding interest, the rule of 73 is more appropriate; for 14%, it would be the rule of 74; for 5%, the rule of 71.

For example, say you have a 22% rate of return (congratulations). The rule of 72 says the initial investment will double in 3.27 years. Since 22 – 8 is 14, and 14 ÷ 3 is 4.67 ≈ 5, the adjusted rule would use 72 + 5 = 77 for the numerator. This gives a return of 3.5, meaning you'll have to wait another quarter to double your money. The period given by the logarithmic equation is 3.49, so the adjusted rule is more accurate.