The cost of cathodic and anodic protection of metallic structures subject to corrosion can be divided into the cost of materials and the cost of installation and operation. Industry data showed that the 1998 sales of hardware components totaled $146 million. The largest share of the cathodic protection market is taken up by sacrificial anodes at $60 million, of which magnesium has the greatest market share. Major markets for sacrificial anodes are the water heater market and the underground storage tank market. The costs of installation of the various cathodic protection components for underground structures vary significantly depending on the location and the specific details of the construction. For 1998, the average total cost for installing CP systems was estimated at $0.98 billion (range: $0.73 billion to $1.22 billion). The total cost for replacing sacrificial anodes in water heaters and the cost for corrosion-related replacement of water heaters was estimated at $1.24 billion per year. Therefore, the total estimated cost for cathodic and anodic protection is $2.22 billion per year.