1/30, I almost always take cold showers after exercise, starting at one though because I don't do it 100% of the time. Unfortunately here the pipes are not very deep so in the summer the water is going to be 70-80 (21-26 C) degrees. In the winter though it comes out around 45-50 (7-10 C). After a couple weeks, and especially after being overheated it really doesn't take that much willpower. At one point I would take a super hot bath in the evening and then take a cold shower right after, it seemed to help get the pump going after a good workout.
I haven't touched my hot water tap in around 2 weeks. After 2min I'm like: "GET ME THE HELL OUT OF HERE." lol