Many scholars argue that Congress should adopt federal rules of statutory interpretation to guide judicial interpretation. This Article uses a novel dataset to show that Congress has long used enacted rules of interpretation and has increasingly done so in recent decades. However, it has chosen to do so on a statute-by-statute basis in a way that has gone mostly unnoticed by scholars and judges. We developed a dataset by using computer code to search the U.S. Code dating back to 1946 for specific phrases indicating a rule of interpretation, then manually checked and classified each rule. These rules not only show that Congress can create interpretive rules, and has become increasingly likely to do so, but they also call into question how we should think about the use of judicial canons. Canons are judge-made interpretive presumptions, and this Article shows that Congress increasingly includes interpretive rules to the same effect in the enacted text of its statutes. For example, one of the most important substantive canons of interpretation is the federalism canon, which tells courts to presume that a federal statute does not preempt state law absent a clear congressional intent to do so. Yet, Congress includes hundreds of rules of interpretation in the U.S. Code that directly address this same issue. Similarly, Congress directly addresses canons like the presumption against implied repeal, presumptions of consistent usage, and many others in enacted statutes. This Article's findings should cause judges and scholars to rethink the use of canons and the justifications for using them.