Recently, I found there are three equations using in calculating CN(curve number) that area "S= 25400/CN - 254" and "S = 1000/CN - 10". In fact, many papers used different equations in their research(just more than these three). I'm wondering the difference bettween "S= 25400/CN - 254" and "S = 1000/CN - 10" and whichis the original one. How can we use them in a correct way.

Ref: https://doi.org/10.1016/j.landurbplan.2021.104195

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