2008, a decrease in emissions of 56 percent. A 2014 EPA analysis estimated that implementation of the Acid Rain Program avoided between 20,000 and 50,000 incidences of premature mortality annually due to reductions of ambient PM2.5 concentrations, and between 430 and 2,000 incidences annually due to reductions of ground-level ozone. Nitrogen oxides In 2003, the Environmental Protection Agency (EPA) began to administer the Budget Trading Program (NBP) under the State Implementation Plan (also known as the "NOx SIP Call"). The Budget Trading Program was a market-based cap and trade program created to reduce emissions of nitrogen oxides (NOx) from power plants and other large combustion sources in the eastern United States. NOx is a prime ingredient in the formation of ground-level ozone (smog), a pervasive air pollution problem in many areas of the eastern United States. The NBP was designed to reduce NOx emissions during the warm summer months, referred to as the ozone season, when ground-level ozone concentrations are highest. In March 2008, EPA again strengthened the 8-hour ozone standard to 0.075 parts per million (ppm) from its previous 0.08 ppm. Ozone season emissions decreased by 43 percent between 2003 and 2008, even while energy demand remained essentially flat during the same period. CAIR will result in $85 billion to $100 billion in health benefits and nearly $2 billion in visibility benefits per year by 2015 and will substantially reduce premature mortality in the eastern United States. NOx reductions due to the Budget Trading Program have led to improvements in ozone and PM2.5, saving an estimated 580 to 1,800 lives in 2008. A 2017 study in the American Economic Review found that the Budget Trading Program decreased emissions and ambient ozone concentrations. The program reduced expenditures on medicine by about 1.5% ($800 million annually) and reduced the mortality rate by up to 0.5% (2,200 fewer premature deaths, mainly among individuals 75 and older). Volatile organic compounds In the United States the Environmental Protection Agency (EPA) classifies Volatile Organic Compounds (VOCs) as gases emitted from certain solids and liquids that may have adverse health effects. These VOCs include a variety of chemicals that are emitted from a variety of different products. These include products such as gasoline, perfumes, hair spray, fabric cleaners, PVC, and refrigerants; all of which can contain chemicals such as benzene, acetone, methylene chloride, freons, formaldehyde. VOCs are also monitored by the United States Geological Survey for