TABLES
EXPLANATION OF TABLE 33
AMORTIZATION OR DEPRECIATION AND REMAINING OR PRESENT VALUE
Table 33 is an amortization table or a set of tables computed
for the interest rates 4 per cent to 7 per cent per annum and for
all terms of indebtedness, terms of bonds or probable life terms
of perishable articles, from 2 to 75 years, which are likely to come
under consideration.
By adding to this table headings at the bottom of the columns
it has also been made convenient for use as a depreciation table.
Care must be taken in its use to preserve the distinction indicated
by the top and bottom headings and not to assume that the
years of expectancy in the last column apply to the age or number
of years noted in the first column.
All values noted in this table are referred to $100 as the basic
amount in order that the figures in the table may be used as
percentages when so desired.
The table has been computed by the use of the following
formule which may be used when values are to be ascertained
for interest rates or terms not covered by the table.
Let a, be the amortization installment which must be invested
 annually in order to amount at compound interest
to $100 in 7 years.
Let 7 be the interest rate expressed decimally (thus o.05 for
5 per cent).
Let A, be the accrued amortization in 7 years when the
annual amortization installment is @, and the interest
rate is s.
Let m be any number of years.
Let n represent the amortization term expressed in years.
Let a, be the current amortization in the mth year, i.e., the
amortization increment a, plus interest on the amortization
 fund already accumulated.
Let ¢ be the remaining years of usefulness of any article
whose probable life new is # years.

= 453