The company-level operating profit markup can be estimated as a power function or a linear function between Net Sales (SALE) and Total Cost = XOPR = COGS + XSGA. The difference between Net Sales and Total Cost (measured by XOPR) is OIBDP (operating income [profit] before depreciation and amortization, or EBITDA). Some analysts include DP (depreciation and amortization) in total cost; however, DP is subject to substantial accounting discretion (such as including acquisition related impairment charges), which can prejudice cross-section comparisons.