It's $5/yr in eth for the actual registration fee. The problem is that the transaction fee gas to register and maintain that registration is steep. So it's fairly common to register your ens for multiple years to save on gas. Once L2's/rollups are more mature and under community control, I expect ens to migrate to one and cut those transaction fees down substantially.

One of my friends got their name for 10 years for $120, so it seems like it fluctuates.