If you could only use one financial statement, which would you use to evaluate an investment?

We should use the cash flow statement, because it tells us the most about a company’s financial health. Cash is king, because we ultimately decide on a company’s value based on its cash flows. The income statement only shows net income, but this is an accounting number and it does not show important cash flow numbers such as changes in net working capital, or cash flows from investing (e.g. capex) or cash flows from financing. The balance sheet shows assets and liabilities in a given year, but it does not show us the performance of the company year to year.