Price per kg nutrient = Price per tonne ÷ 10 ÷ % nutrient Example 1: Paddock has high phosphorus (P) and low sulfur (S) so need to apply sulfur. Apply Calculation C. Single superphosphate 262/t ÷ 10 ÷ 11% S = per kg sulfur Gypsum 56/t ÷ 10 ÷ %S = per kg sulfur