The present invention provides a method and system for determining a toll charge for vehicles traveling on a toll lane that includes determining a change in traffic flow for vehicles traveling on the toll lane, determining a change in traffic speed for vehicles traveling on the toll lane, and determining the toll charge for vehicles traveling on the toll lane using a weighting approach that weights the change in traffic flow with a first factor and weights the change in speed with a second factor, the first factor depending on whether the change in traffic flow is increasing or decreasing, and the second factor depending on whether the change in speed is increasing or decreasing.