1. A method comprising: calculating miles traveled by one or more vehicles along a predefined route; calculating a fuel usage of the vehicles for traveling along the route to obtain one or more fuel values; analyzing data indicating the miles traveled and the fuel values to determine fuel efficiency values corresponding to the vehicles traveling the route; and determining an estimate of an amount of carbon emissions for each of the vehicles based in part on applying at least one carbon emission value to respective fuel values associated with corresponding determined fuel efficiency values.