The Union of Concerned Scientists (UCS) today launched a new web feature that tracks the estimated net benefits of the Clean Air Act from when it became law in 1970. The “ticker” is based on Environmental Protection Agency (EPA) estimates of the law’s net health and economic benefits.

By preventing premature deaths and reducing the harmful effects of air pollution, the Clean Air Act has proven to be a smart investment. In 2010 alone, the law generated environmental and health benefits estimated at $1.3 trillion (in 2006 dollars), according to the EPA. The estimated cost of compliance that year was $53 billion (in 2006 dollars), making the law’s estimated net benefit $1.247 trillion and its benefit-cost ratio approximately 25 to 1.

The EPA estimates that the law’s benefit-cost ratio will be 30 to 1 by 2020, when, according to the federal agency’s projections, the law would prevent as many as 230,000 premature deaths in that year alone.

The ticker starts with an estimate of the cumulative net benefit of the law from its inception in 1970 through today, which amounts to more than $48 trillion (in 2010 dollars). It will continue to count net benefits every second and reach $65 trillion in 2020, based on EPA estimates. The ticker can be embedded on other websites and blogs, as well as shared on Facebook and Twitter.

The web feature also includes an explanation of the methodology and sources UCS used for the ticker’s calculations.