Why are bricks so expensive?

I've been noticing lately that the price of bricks has been skyrocketing. It seems like just a few years ago, bricks were a lot more affordable. So, I have to ask, why are bricks so expensive now? Is it a supply and demand issue? Have the costs of production gone up significantly? Or is there something else going on in the market that's driving up the prices? It's a mystery to me, and I'm sure many others are wondering the same thing. Can you shed some light on this for us?