We have now made it past Joe Biden’s first 100 days in office, the traditional point at which political journalists pass sage judgment on the early results of a new presidency (or at least tap out a few saved-up think pieces in need of a hook). The country owes this practice to Franklin Roosevelt, who in July of 1933 sat down for one of his early fireside chats and told radio listeners that he wanted to reflect on “the hundred days which had been devoted to the starting of the wheels of the New Deal.” Reporters have been using it as a benchmark for taking stock ever since.

Does the custom still make any sense today? Maybe. Some research has found that presidents really have had more success passing legislation during their first 100 days than later on, possibly because they have tended to enjoy a moment of bipartisan approval early in their terms. These honeymoon periods might be thing of the past, however, thanks to increasing partisan polarization, which means the first three months might not matter in quite the same way they used to.

But whether or not it makes practical sense,marking the first 100 days bugs me purely from the standpoint of historical appreciation. FDR’s first 100 Days, momentous as they were, are arguably a tiny bit overrated in the popular imagination. And the focus on them obscures the fact that Roosevelt truly cemented his domestic legacy in a period known as the Second 100 Days—which took place two years later, in 1935. That’s when we got little things like Social Security and the foundation of modern labor law. The commentating class basically ignores that stretch, rather than think about what lessons it might hold.

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Which brings us to the second 100 days. In theory, the demise of the National Industrial Recovery Act could have cowed the administration, as the Supreme Court seemed poised to begin striking down much of the New Deal. But instead, Roosevelt chose to pursue a new, bold course of action. In June of 1935, he called another special session of Congress, and laid out four “must-pass” pieces of legislation: A new labor plan from Sen. Robert Wagner, a banking bill, a law aimed at breaking up large utility holding companies that were seen as monopolistic menaces sitting atop the electricity sector, and—most crucially—his social security proposal. Later, he added a tax bill designed to “soak the rich.” All passed, though the tax bill was watered down quite a bit.

Without these accomplishments, the New Deal would have been an impressive effort of economic firefighting and expansion of federal power, with some lasting legacies like banking deposit insurance and securities regulations. With them, Roosevelt laid down the bricks of a truly transformative legacy. (Historians often refer to his domestic accomplishments from 1935 on as “the Second New Deal.”) Most momentous was the Social Security Act, which would undergird the modern welfare state, creating our national system of old-age pensions and unemployment insurance as well as aid programs for the children of widows and the blind. The Wagner Act—aka the National Labor Relations Act—became the cornerstone of U.S. labor law. The banking bill essentially created the structure of the modern Federal Reserve, centralizing power over monetary policy with the presidentially appointed Board of Governors. The holding company bill breathed new life into the antitrust movement, and signaled a philosophical break with the thinking that had birthed the NIRA.