Please let me try to help.
If i'm not mistaken , you lease on to FXCC , that's gives you .31 C discount on the fuel at the Barstow TA.
C.A Fuel Tax , that come str8 out of your quarterly taxes ,(there for you actually don't pay), is : .437C
if you are getting just around 10 MPG .
than the actual cost for fuel for you is : 21 C/M.
it's up only 3 to 4 C in the last few months.
and your rates probably gone up in a greater phase .
it will hardly effect your cost of doing business.
it will however greatly effect your cost of DH , driving without a pay, out of route millage ,idling & reefer if apply .