Glad to see I'm not the only OCD spreadsheet compiler
I bought a little dual-sport motorcycle (Kawasaki KLR 250) about 3 months ago. Since I got the bike I drive my Ranger (stick 2WD 4 banger) about 1/3 the miles I used to. The KLR only gets ~45 mpg, which is a lot less than it should. I think it's likely a combination of the aftermarket muffler that a previous owner installed, knobby tires, and a front brake that seems to stick a bit. But still twice as much as the Ranger (22 mpg w/ canopy).
Based on my spreadsheet figures, since I got the motorcycle I've reduced my gasoline consumption by the annual equivalent of 49 gallons. And that includes the "take back effect" of having a more fuel efficient vehicle. I have definitely been driving the motorcycle a lot more than I would my Ranger, not really because it's more fuel efficient, but because it's fun as hell. It's given me the excuse to explore a bunch of local back roads, I feel like I have a much better lay of the land since I got the bike.
I'll be interviewing for a job that will require me to commute (I currently live at work). I don't look forward to having to commute, but the job pays 50%+ more per hour, has good bennies, and much better long-term prospects than my current job. The motorcycle should be even handier if I have to commute, reduce my vulnerability to rapid gas price spikes.
A garden will make your rations go further.