These non-GAAP measures allow management and investors to view operating trends, perform analytical comparisons and benchmark performance between periods and among geographic regions to understand operating performance without regard to items we do not consider a component of our core operating performance. Furthermore, these non-GAAP measures allow investors the opportunity to measure and monitor our performance against our externally communicated targets and evaluate the investment decisions being made by management to improve ROIC-adjusted. Management uses these measures in its financial, investment and operational decision-making processes, for internal reporting and as part of its forecasting and budgeting processes. Further, our Board of Directors uses these and other measures as key metrics to determine management performance under our performancebased compensation plans. For these reasons we believe these non-GAAP measures are useful for our investors.
EBIT-adjusted is used by management and can be used by investors to review GM's consolidated operating results because it excludes automotive interest income, automotive interest expense and income taxes as well as certain additional adjustments that are not considered part of our core operations. Examples of adjustments to EBIT include but are not limited to impairment charges related to goodwill, impairment charges on long-lived assets and other exit costs resulting from strategic shifts in our operations or discrete market and business conditions; costs arising from the ignition switch recall and related legal matters; and certain currency devaluations associated with hyperinflationary economies. For EBIT-adjusted and our other non-GAAP measures, once we have made an adjustment in the current period for an item, we will also adjust the related non-GAAP measure in any future periods in which there is an impact from the item.
EPS-diluted-adjusted is used by management and can be used by investors to review GM's consolidated diluted earnings per share results on a consistent basis. EPS-diluted-adjusted is calculated as net income attributable to common stockholders-diluted less certain adjustments noted above for EBIT-adjusted and gains or losses on the extinguishment of debt obligations on an aftertax basis as well as certain income tax adjustments divided by weighted-average common shares outstanding-diluted. Examples of income tax adjustments include the establishment or reversal of significant deferred tax asset valuation allowances.
ROIC-adjusted is used by management and can be used by investors to review GM's investment and capital allocation decisions. GM defines ROIC-adjusted as EBIT-adjusted for the trailing four quarters divided by average net assets, which is considered to be the average equity balances adjusted for average automotive debt and interest liabilities, exclusive of capital leases; average automotive net pension and OPEB liabilities; and average automotive net income tax assets during the same period.
Adjusted automotive free cash flow is used by management and can be used by investors to review the liquidity of GM's automotive operations and to measure and monitor our performance against our capital allocation framework and evaluate our automotive liquidity against the substantial cash requirements of our automotive operations. GM measures adjusted automotive free cash flow as automotive cash flow from operations less capital expenditures adjusted for management actions, primarily related to strengthening its balance sheet, such as prepayments of debt and discretionary contributions to employee benefit plans.