How to read and return percentage range

[Shefkat]

If  a field (composition in product (silk, cotton, etc.) and another field (content) is given as percentage range e.g. for silk it is < 0.025% or  for cotton is 0.05 < 0.25 % how can I turn this field (content) into some other numerical field.

e.g. if composition in product (silk, cotton) then content (silk) is given as < 0.025% write 1, if 0.05 < 0.25 %  write 2 etc. then i will try to plot a graph of composition in product vs. content such as silk in a range of 1 to 2 and cotton is a range in 2 etc.

Basically, I need to transform given information in percentage range to a number

[G3S]

It might be an if statement if the products are small in number, otherwise either an inline table or an attached file outlining the product and the range