Zcash was originally created as a fork of the Bitcoin code base, so it holds many of the same financial properties, like scarcity. There will never be more than 21 million Zcash in circulation — same as Bitcoin — so, when demand for Zcash increases, the price increases. As new coins are mined into circulation, inflation goes down, and at each halvening the rate drops significantly. Zcash inflation almost precisely mimics that of Bitcoin.