Financial ratios are useful tools for investors to better analyze financial results and trends over time. These ratios can also be used to provide key indicators of organizational performance ...
Bruns, William J., Jr. "Introduction to Financial Ratios and Financial Statement Analysis." Harvard Business School Background Note 193-029, August 1992. (Revised September 2004.) ...
But to really dig down into the valuation of a stock you'll want to understand some key financial ratios to compare the health of a company with its peers, its industry and itself over time.