SEMAINE D'ÉTUDE SUR LE ROLE DE L’ANALYSE ECONOMETRIQUE ETC. 
A3G 
ment or the rate of profit have undergone considerable varia- 
ons, as shown, for example, by a coefficient of dispersion. 
But the important point is that such a dispersion, if it has 
taken place, has done so around a roughly constant trend. 
The result is that, after a century of vicissitudes, these magni- 
tudes are in 1960 practically at the same level as they were 
in 1860. The case of population, per-capita income, or com- 
position of demand, is radically different. These quantities may 
have changed very little from one year to another but they 
have always changed in the same direction. The cumulative 
result, after a century, is enormous. Population has increased 
five times, per-capita income has also quintupled, and total 
consumption is mostly composed in 1960 of goods and services 
that in 1860 did not even exist: in other words, the trends of 
these variables have been irreversibly and persistently increas- 
ing, and are going to persistently increase in the future. 
To conclude, the distinction between variables and cons- 
lants in the present analysis has been based on variability 
chrough time. Therefore, it does not coincide, and must not 
be confused with, the distinction between unknowns and data, 
namely between quantities which are intended to be explained 
and quantities which are accepted as given from outside eco- 
nomic analysis. Accordingly, there are magnitudes — such 
as population and technical progress — which are here taken 
as given from outside economics and nevertheless are essential 
variables. And there are other magnitudes, like the rate of 
profit, which are to be explained by economic investigation, 
and which nevertheless have been taken as constant over time. 
10] Pasinetti - pag. bo-