They are made at a constant predetermined rate. They are only harder to make because more people are trying to make them. The way bitcoins work is that the di

They are made at a constant predetermined rate. They are only harder to make because more people are trying to make them. The way bitcoins work is that the difficulty of the proof scales with the CPU power. If half the computers currently mining decided to move on to do something else tomorrow, bitcoins would continue to be made at the exact same rate.