TARLES 
EXPLANATION OF TABLE 22 
CoMPOUND INTEREST 
Amount of one dollar at interest compounded annually 
In Table 22 the amount is given of $1 at interest rates from 
I to 10 per cent, interest being compounded annually for any 
number of years up to roo. 
The formula on which this table is based is the following: 
Let A’ represent the amount at the end of nth year of $1 plus 
interest compounded annually. 
Let n represent the number of years. 
Let 7 represent the interest rate expressed decimally as 0.03 
for 5 per cent. 
Then 4’ = (a + I)" (19) 
Example. — What is the amount in 7 years of $400 at 6 per 
cent interest compounded annually? 
From Table 22 the amount of $1 at 6 per cent interest in 7 
years is found to be $1.503630 and the amount of $400, therefore 
$400 X $1.503630 = $601.45. 
The section of Table 22 covering interest rates in excess of 
10 per cent will be found serviceable for certain special purposes 
such as the determination of the present value of mining proper- 
ties. This section of the table has been abbreviated by the 
omission of certain individual years but it can nevertheless be 
made to serve in finding the amount of $1 at compound interest 
for any year by going into the table with any two years whose 
sum is equal to the number of years for which the amount is to 
be determined and obtaining the product of values found in the 
table for these two years. This product will be the required 
amount. 
Example. — What is the amount of $1 at 15 per cent com- 
pound interest in 46 years? 
The amount of $1 for 16 years at 15 per cent is found to be 
$9.357621. 
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