If someone offered you an investment that would pay out $25 for every $1 you paid you would probably take it.

It turns out that investing in clean air generates exactly those returns in health benefits to the American public. The rules that keep our air safe to breathe raked in annual benefits of $1.3 trillion compared to costs of only $53 billion in 2010. Things like avoided doctors’ visits, increased property values, and pollution-related deaths postponed add up to major money in the pockets of families around the country.

At a time when the Clean Air Act is under attack in Congress, these figures make you wonder what legislators mean when they say the rules are too expensive. Threats to gut the government’s ability to implement the law come from anti-regulatory interests that complain of compliance costs but make no mention of the price pollution imposes on the public.

EPA recently released a study evaluating the costs and benefits of amendments to the Clean Air Act between 1990 and 2020. The report scours the gritty details of how much pollution is reduced and what that means for human health and the economy. No surprise: the cleaner our air, the more economic benefits we get.

The majority of benefits come from reductions in mortality, or early deaths, quantified using what’s known as the Value of a Statistical Life (VSL). The VSL measures how much people are willing to pay for small reductions in the risk of mortality. It is typically estimated by looking at how much you have to pay someone to take a more dangerous job. For example, one study found that after carefully controlling for occupational differences, the average employee would require an extra $12,200 (in 2006 dollars) a year in wages to take a job with a 0.2% higher chance of an on the workplace fatality. That works out to a value of a statistical life of $6 million.

To calculate the benefits of clean air regulations, the EPA uses a value of $7.6 million for the VSL per early death avoided. The agency estimates that the amendments to the Clean Air Act will prevent 230,000 deaths a year by 2020, for a benefit of $1.7 trillion–nearly 80% of the total projected benefits of the rules for that year.