Status of the Nation's Highways, Bridges, and Transit:
2002 Conditions and Performance Report
Exhibit C-1 is a chart that shows asset decay curves. The vertical axis measures asset condition from 0 to 6 and the horizontal axis measures progressive age, though without numbers. There are three lines, all starting at condition 5. The first line, for linear, goes in a straight line to 1 as an asset ages. The second line, for logistic, stays between 4 and 5 for a while before sloping sharply to 1 as an asset ages. And the third line, for logit, drops sharply to 3 early on then slopes gradually to 2 as the asset ages.
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