SEMAINE D ETUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 861

period of time equal to Ô, total production is equal to consumed
 income plus invested income, and the corresponding
investment is completely used up during the following period.
In the first period, the share of R,(¢#) which appears in consumed
 income is (1 - A), while A is invested. In the second
period, the share of primary income R,(f) which appears in
consumed income is A(x - A) while 22 is invested. In the n°”
period, the fraction of primary income R,(f) which appears
in consumed income R” of that period is given by (!)

an-1 (1 - 2) -

Thus, as a result of this process, the amortisation schedule
of primary income is of exponential form, and that over a

period of length ®, the amount of non-amortised primary income
 is reduced in the ratio of 1 to À. It follows that if the
formulation of the exponential model is taken as exact, the
share À of primary income incorporated in investment is

since © is the lengh of the amortisation per:oc.

i

|

=4..

Te
vi

50

Naturally we have

=),

A) G+FA+

4.

[11] Allais - pag. 165