The TRI program has expanded significantly since its inception in 1987. The Agency has issued rules to roughly double the number of chemicals included in the TRI to approximately 650. Seven new industry sectors have been added to expand coverage significantly beyond the original covered industries, i.e. manufacturing industries. [TRI reporting industries primarily include manufacturing, metal and coal mining, electric utilities, and commercial hazardous waste treatment. Mobile sources emissions, which account for approximately 50% of all air toxics, as well as smaller sources such as gas stations and dry cleaners are not included in TRI.] Most recently, the Agency has reduced the reporting thresholds for certain persistent, bioaccumulative, and toxic (PBT) chemicals in order to be able to provide additional information to the public on these chemicals.