How often do air traffic controllers retire?

I would like to become an ATC next year, but I don't think it's possible. I don't have a degree, but I've read you can become an ATC if you have 3 years of progressive work experience. To my understanding, positions open when workers retire. I read somewhere that there was a shortage at one point and they were just hiring the average joe without a degree (I'm sure they were somewhat selective and didn't just hire anyone). My question is, will there be many people retiring within the next 2 years for there to be a need for ATCs without the degree?