[tachibana]

From my accounting background, some common ratios I use:

1) acid ratio (liquid assets / short term liabilities)

2) gross operating margin

3) net operating profit margin

4) return on capital/equity

5) return on balance sheet assets

I also compare the stock in question to other bonds and stocks of other companies similar in size or industry. This is just to see if the company is managing its money well in relation to other companies.

Finally, tax consequences of sale. The conventional wisdom of market returns of 11% (US treasuries + 8% * portfolio beta , 1.0 for market portfolio) loses its appeal if your tax bracket is sufficiently high (i.e. software engineer in California) .