Microsoft Corporation's return on equity: 3 definitions, 3 answers

The same balance sheet, read 3 ways

The lowest of these is 30.23% and the highest is 34.04%, a factor of 1.13. All of them are arithmetically correct. They are answers to different questions, and the column above says which question each one answers.

Net income over closing equity

A full year of profit over the equity standing on the last day of it. The most commonly published of the three, and the one that moves most when a company buys back stock late in the year. Read from Net income 133.75 bn USD, Total stockholders' equity 442.39 bn USD.

Net income over average equity

The textbook definition. Profit earned over a year is matched against the equity that was employed across that year, so it needs the prior year's balance sheet and cannot be computed for a company's first filed year. Read from Net income 133.75 bn USD, Total stockholders' equity 442.39 bn USD, Total stockholders' equity (prior year) 343.48 bn USD.

Net income over total equity including minority interests

Adds the equity held by outside shareholders in consolidated subsidiaries. Identical to the closing figure where a company has no minority interests, and materially lower where it has large ones. Read from Net income 133.75 bn USD, Total equity 442.39 bn USD.

And our own figure. The number this product prints for MSFT is 30.23%, computed as netIncome divided by total equity, taking totalEquity where the filer reports it and totalStockholdersEquity otherwise. That is the net income over closing equity line above.