jurisdictions have used a variety of metrics to determine the emission benefits of carbon taxes. One of the most rudimentary metrics for measuring carbon tax effectiveness is overall reductions in GHG emissions that can be tracked using GHG emissions inventories at the national or local level. This metric is flawed in that it captures not only the carbon tax effects but also the effects of other carbon mitigation polices and exogenous variables such as the level of economic growth. While this metric lacks precision, jurisdictions can use it to evaluate whether they are meeting overall GHG reduction goals and to determine whether policies, including carbon taxes, should be modified accordingly