The net cash a company generates minus its business and investment expense. Generally defined as all revenue less all operating expense.
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Operating cash flow does not involve items like taxes and insurance payments because they cannot be used to help conduct daily business.
This is the most important barometer of a company’s financial health because it indicates how much money is available for maintaining business, in both the present and the future. A company that does not generate cash over the long term will die out over time.