Performance measures demonstrate how well the transportation system is doing its job of meeting public goals and expectations of the transportation network. Some methods used to measure performance include tracking average speeds and crash rates. Many states and metropolitan areas monitor how close they are to achieving specific goals, such as accessibility to key regional population, employment, cultural, and recreational centers, the mobility of disadvantaged populations, levels of air quality, and the health of the economy, by using performance measures.
Measuring performance is a way to gauge the impacts of the decisionmaking process on the transportation system. Performance measures aim to answer questions about whether the performance of the transportation system (or economy, air quality, etc.) is getting better or worse over time; and whether transportation investments are correlated or linked to stated goals and outcomes.