slope in HRU definition

[navee...@gmail.com]

Hi,

I have a doubt about what should be used for slope classes in HRU definition. Is it  (percentage increase in slope) or (% of slopes that fall in a class). Which one is used?

For example, in my area percentage increase in slopes varied from 0 to 375. I found three classes to be relevant from (0 to 12%; 12 to 33%; and 33 to 375%). It is that first class occupies 0 to 3%; 3 to  10%, and 10 to 100 % of the slope map.

My question is should i take 

(0 to 12%; 12 to 33%; and 33 to 375%)

or

(0 to 3%; 3 to  10%, and 10 to 100 %) to define slope class.

best,

naveen