The basic goal of the Three-Year Plan, officially named "The Three-Year Post-war Reconstruction Plan of 1954–56", was to reconstruct an economy torn by the Korean War. The plan stressed more than merely regaining the prewar output levels. The Soviet Union, other East European countries and China provided reconstruction assistance. The highest priority was developing heavy industry, but an earnest effort to collectivize farming also was begun. At the end of 1957, output of most industrial commodities had returned to 1949 levels, except for a few items such as chemical fertilizers, carbides, and sulfuric acid, whose recovery took longer.