The equivalent term used in the Montreal Protocol is consumption. Ozone-depleting potentials for the chemicals represented in the indicator are shown in Table 2 . Annual values for the Canadian GDP are also shown in Table 1 . GDP has been indexed to the 1992 Canadian dollar value. While accounting periods do not necessarily correspond with government reporting requirements, there is no evidence that considerations such as this have distorted the annually or quarterly reported amounts of ozone-depleting substances in the new supplies to any significant extent.
Chlorofluorocarbons are a group of organic chemicals containing carbon, fluorine, and chlorine.
Halons are chemicals similar to CFCs that contain the element bromine, but not necessarily chlorine. Hydrochlorofluorocarbons contain hydrogen in addition to carbon, chlorine, and fluorine. Methyl bromide is a broad-use agricultural soil fumigant, and it is also used after harvesting to eliminate insects and rodents that contaminate fruits, vegetables, and grains. Methyl chloroform is a metal-cleaning agent. 1.000 CFC-115 0.