Anyone ever figure out your engines fuel consumption over an entire year? I am wondering what the average might be per hour to add that in as a straight cost per hour to the customer (simply included in my hourly rate). I am unsure if fuel consumption can change from a brand new mower to one that has 1200-1500 hours on it, or does the engine continue to operate on a similar efficiency for its entire life. My specific mower and engine I have is a Ferris IS1500Z with a 25hp Kawasaki, I have not been grinding and bagging leaves this year but next year I will. How will that affect my fuel usage with the extra processes and workload? This year I put 52 hours on my machine (I know guys thats not a lot of hours, but understand I only had 6 accounts and my own lawn, and I am a full fledged landscape company who just started this year in the lawn maintenance) and I have a pretty accurate log of 60 gallons of fuel used. Anyone with a similar mower and engine or the exact one?