(a) Any commercial fertilizer shall be deemed deficient if the analysis of any primary nutrient is below the guarantee by an amount exceeding the values in the following schedule:

For guarantees not listed, the appropriate values shall be calculated by interpolation.

(b) Any commercial fertilizer shall be deemed deficient if the analysis of any secondary or minor elements is below the guarantee by an amount exceeding the values in the following schedule:

The maximum allowance when calculated in accordance with the above values shall be one unit (1%).