To supplement our financial results presented in accordance with GAAP, this release includes the following measures defined by the Securities and Exchange Commission as non-GAAP financial measures: pro forma net income (earnings) per share, pro forma effective tax rate and free cash flow. These non-GAAP measures are not based on any comprehensive set of accounting rules or principles and should not be considered a substitute for, or superior to, financial measures calculated in accordance with GAAP, and may be different from non-GAAP measures used by other companies, limiting the usefulness of the measures for comparison with other companies. Management believes providing investors with an operating view consistent with how it manages the Company provides enhanced transparency into the operating results of the Company, as described in more detail by category below.

The tables below provide reconciliations between the GAAP and non-GAAP measures.

Pro forma effective tax rate

The Company’s income tax expense is periodically impacted by discrete tax items that are not reflective of income tax expense incurred as a result of current period earnings. Therefore, management believes disclosure of the effective tax rate and income tax provision before the effect of certain discrete tax items are important measures to permit investors' consistent comparison between periods. In the first quarter 2020 and the first half of 2019, there were no such discrete tax items identified.