Currently with PoW, Ethereum supply is indeed infinite and growing quickly but the coin might evolve during the year to become a PoS coin.

https://blockonomi.com/ethereum-casper/

This would change a lot of things, and I'm interested to see to where the price will be driven. I think a lot of users likes ETH because of its mining profitability, so where all these miners will come once ETH will be switched ?

Currently I don't really know if PoS will reduce inflation, but that's quite sure.

Btw, I've found a thread showing ETH inflation during 2017 :

https://ethereum.stackexchange.com/questions/12501/what-is-ethereums-inflation-rate-how-quickly-will-new-ether-be-created