We recently took a road trip in our 2007 Honda Civic.
We travelled 1191 miles using approximately 29.966 gallons of gasoline. Based on the totals, the mileage we achieved was approximately 39.7 miles per gallon.
Here is a chart of our distance and gas usage that I recorded over several days. Based on a linear regression, our best-fit mileage is 39.46 mpg.
This was almost all highway driving, but it still seems surprisingly good, considering the new Honda Civic is supposed to get 36mpg highway.
Here are the data that I recorded to measure our mileage. The Price and Gallons data from Ontario are converted from litres.| Date | State/Province | Price/gallon | Odometer | Gallons | Mileage |
| 07/25/08 | NJ | 3.899 | 10736 | Full | N/A |
| 07/26/08 | NY | 4.329 | 11080 | 8.775 | 39.2 |
| 07/30/08 | ON | 4.652 | 11346 | 6.908 | 38.5 |
| 07/31/08 | NY | 4.329 | 11570 | 5.985 | 37.4 |
| 08/02/08 | NJ | 3.859 | 11927 | 8.298 | 43.0 |