Total population was 93 million in 1960. Assuming GDP to be per capita income times population (assuming investment is low), thats GDP of around 318 times 93 million = 30 billion rupees.
A year spending in this period was about 2000/5 crore rupee = 400 crore = 4 billion rupees.
Implying 4/30 = about 13% extraction from economy to spend (not really true given the foreign aid, but lets go with it as a max frontier amount).
But wait what about the inflation of PKR from 1960 to 1975 (which I am assuming is the rupee reference year being used) given the denominator being used is 1960 prices? Total inflation in the time period seems to add up to 3 times:
https://data.worldbank.org/indicator/FP.CPI.TOTL.ZG?locations=PK
Thus the actual extraction rate we are talking about is more like 4 - 5% at most (foreign aid % + investment denominator component reduces it even more). Basically in the vicinity of 95% of the money is left alone inside West/East Pakistan to begin with.....and your issue is focusing on the 5% being skewed to one side. Its negligible (given the actual materialisation on both wings takes further chunks out of it given poor state of bureaucracy and transparency and accountability etc)....and more than compensated by the institutional development Pakistan was attempting at the time (which really has no direct money value) to improve the delivery mechanisms first before committing larger extraction (this is economics 101 that the top economic minds on all sides of the cold war argument fundamentally knew).
Its no surprise that Pakistan is charging ahead in improving on the corruption perception index today, and you are left way behind stagnating over last 5 years or more.
@Chak Bamu @farhan_9909 @django