Item Category Determination for Material Determination

Reference: link

Header level pricing 
OR + NORM + PSHP + [Item Usage]   = TAX  (Main Item)OR + NORM+PSEL+TAX  = TAPS (Sub Item)

Item level pricing 
OR + NORM + PSA1 + [Item Usage]   = TAPA  (Main Item)OR + NORM+PSA2+TAPA  = TAN (Sub Item)