The Second Plan focused on the development of the public sector and "rapid Industrialisation". The plan followed the Mahalanobis model, an economic development model developed by the Indian statistician Prasanta Chandra Mahalanobis in The plan attempted to determine the optimal allocation of investment between productive sectors in order to maximise long-run economic growth. Hydro electric projects and five steel plants at Bhilai, Durgapur, and Rourkela were established with the help of Russia, Britain (the U.K) and West Germany respectively. Coal production was increased. More railway lines were added in the north east. The total amount allocated under the Second Five-Year Plan in India was billion. This amount was allocated among various sectors: power and irrigation, social services, communications and transport, and miscellaneous. The second plan was a period of rising prices. The country also faced foreign exchange crisis. The rapid growth in population slowed down the growth in the per capita income.