The article explores how capital accumulation and private information about productivity affect economic efficiency. By linking current and future payoffs to productivity reports, efficient risk-sharing is achieved. The study shows that in this setup, more capital is allocated to individuals with a history of high productivity, even if the expected productivity is the same for everyone. This allocation leads to voluntary long-term participation and does not require transfers between different wealth groups. The findings suggest that efficient risk-sharing can be achieved through fair insurance contracts, with implications for the risk-free interest rate in the economy.