Your water provider most likely bills by the 1000’s of gallons. Do you get billed monthly or quarterly? If it’s quarterly I would say based on the little bit of information you provided, that should be about right. You may have just used more water last year when compared to this year which does happen. If it is monthly, you were using a lot of water last year, you may have had something leaking and had fixed the issue at some point. My normal suggestion when anyone asks about high usage, always check your toilets for possible leaks. You can get small dye kits to test, or if you have some cold/ room temp coffee, you can use it to do the same test.