1174 PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28 
In his March, 1962 speech KRUSHCHEV also noted that the 
deliveries of certain farm machines declined substantially be- 
tween 1957 and 1960. However, there appears to have been 
a substantial increase in farm machinery production since 
1960 - perhaps by 50%. 
C. General Comment 
It is fairly obvious from the above brief discussion of 
projections, goals, and performance that much remains to be 
achieved before specific projections of output and consumption 
are to provide an adequate base for development plans. It can 
be argued, of course, that either inadequate analytical and 
statistical methods were used or that the goals were politically 
motivated. Such an argument could be correct, but it implies 
that more adequate methods are available and could be applied 
in specific cases and that the political elements can be eli- 
minated. 
IV. SOME ANALYTICAL AND STATISTICAL PROBLEMS 
For short periods of time, say three to five years, it ap- 
pears that fairly accurate projections of changes in the demand 
for agricultural products are possible. However, even this 
statement must be qualified to exclude such effects as the Ko- 
rean War or a significant change in the policies of other im- 
porters or exporters where international trade is involved. 
Projections of changes in output or of the effect of specific 
policy measures upon output are subject to much greater uncer- 
tainty. Even if we exclude the problems that may arise be- 
cause of climatic variations, other determinants of output do 
not appear as yet to be subject to reasonably adequate projec- 
16] Johnson - pag. 34