A few key facts about the relationship between transportation policy and health:

In the United States traffic fatalities kill just over 40,000 per year, costing the nation $230.6 billion, or 2.3 percent of the gross domestic product, since 2000.

People in more compact metropolitan areas suffer from significantly fewer chronic medical conditions than their counterparts in more sprawling regions. For example people who live in neighborhoods with a mix of shops and businesses within easy walking distance have a 35 percent lower risk of obesity.

Each year air pollution triggers over a million asthma attacks, more than 47,000 cases of chronic bronchitis in adults and 540,000 cases of acute bronchitis in children and kills 70,000 people.

Vulnerable populations, such as seniors and minorities, who cannot or choose not to drive have a higher risk of being killed as a pedestrian. African-Americans make up approximately 12 percent of that population, but they account for 20 percent of pedestrian deaths. Native Americans are 1.5 times more likely to die from traffic crashes than anyone else.

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