Modern coining methods have vastly reduced the frequency of these varieties due to the use of a single squeeze hubbing method during die creation, but doubled dies in modern United States coinage are still occurring. With the new die making process, implemented after 1996, dies only required one impression of the hub to transfer all of the design from the hub to the die. But it has been discovered that the pressure created is so great, that some dies tend to slightly rotate during this process.