My 06 coupe averages around 23.5 in town

My wife and I took a trip to yellowstone , Came back thru Vegas and Phoenix
( a little over 4700 miles ) averaged a little over 31. ( 6 speed staying at the speed limit)

If I factor in that I am running 255/40/19 ( at 30 miles I actually cover a little over 31 miles)

So using this I was getting a little over 32 mpg. Lowest was a little over 29 mpg. Highest a little over 35 mpg.

I purchased some off brand additive from the Dollar store for one Dollar. Used it every time I more put then 10 gals in the tank. >

Calculated that the additive gave me adout 2 more mpg.

Thanks Ray