The calculation is made based on Microsoft's 8-K statement with the U.S. Securities and Exchange Commission (SEC) on July 22. Calculations by ComputerWorld show Surface sales resulted in a loss of $363 million last quarter, the largest one-quarter loss for Surface since Microsoft began providing quarterly revenue figures. The 8-K report also reveals that Microsoft took a write-off due to a decision to not ship a new form factor, this likely refers to the cancelled Surface Mini tablet.
Without a cost of revenue figure, it is impossible to calculate a precise gross margin, a rough measurement of profit. However, using information in the 10-K that Microsoft filed last Friday, along with data from earlier reports, it is possible to estimate Surface cost of revenue.Source: Computer World
Calculations by Computerworld show that the Surface's cost of revenue for the June quarter was $772 million. With revenue of $409 million, that put the tablet in the red to the tune of $363 million, the largest one-quarter loss for the Surface since Microsoft began providing quarterly revenue numbers.