168 
PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 2¢ 
These are the various relations for a stationary process given 
in my 1947 book « Economy and Interest » (!) (3). 
Primary Capital 
I4I. In a stationary process, the average amortization pe- 
riod is equal to the quotient derived by dividing capital by 
amortization, whatever the amortization rules. It follows that 
for primary capital C, we have 
(I4I-I) 
C.=0R,. 
From the earlier expression for C (3) and for a given func- 
fon ¢(0), C, can be derived by putting i=0. Thus we have 
(I41-2) 
Co lim P elr 
=m € -Tw(e)do 
rr 0¢(6)d6 
and this is effectively relation (141-1), (relation 112-I). 
Thus ® can be regarded as the average amortization period 
of primary capital (4). 
(!) « Economy and Interest », pp. 127, 128, 132, 133, 187 and 188. 
(3) The hypothesis that k=1 is made implicitly in this study; the func- 
tion (6) there considered is the same as Rw ©(A) in the notation of the 
present paper. 
(3) Relation (140-7). 
(*) Of course this equality also holds as a first approximation for small 
values of n (relation 126-10) 
111 Allais - pag. 72