When we look back in the history of Railroad Retirement, we know that Railroad Retirement was started before Social Security even began. However, in time it became more integrated. In 1951, a financial interchange was established between the two. In 1965, a provision was created to coordinate the tax rates and allow Medicare to expand and cover those in the Railroad Retirement system. In 1974, the Railroad Retirement Act split the Railroad Retirement benefit into Tier I and Tier 2, with Tier 1 is designed to be equivalent to the benefits offered by Social Security.