.s . gaap is available in item 8 of this report . free cash flow management internally uses a free cash flow measure : ( 1 ) to evaluate the company 2019s operating results , ( 2 ) to plan stock buyback levels , ( 3 ) to evaluate strategic investments and ( 4 ) to evaluate the company 2019s ability to incur and service debt . free cash flow is not a defined term under u.s . gaap , and it should not be inferred that the entire free cash flow amount is available for discretionary expenditures