378 VALUATION, DEPRECIATION AND THE RATE-BASE
When the annuity is applied at the beginning instead of at the
end of the year and is called a,” then:
a) = * =)
i RE le
or, by the aid of equation (23)
iT:
ay’ = Zr (250)
These values are readily found with the aid of Table 26, it
being remembered that A" is the value appearing in that table
reduced by 1 (one).

(25,