This article presents new estimates for investment and new growth accounts for three socialist economies between 1950 and 1989. Government statistics reported distorted measures for both the rate and the trajectory of productivity growth in Czechoslovakia, Hungary, and Poland. Researchers have benefited from revised output data, but have continued to use official statistics on capital input, or estimated capital stock from official investment data. Investment levels and rates of capital accumulation were much lower than officially claimed and over‐reporting worsened over time. A setback in factor accumulation—both investment in equipment and labour input—contributed very significantly to the socialist growth failure of the 1980s.