MOSAIC CO | 2013 | FY |

10. GOODWILL

Goodwill is carried at cost, not amortized, and represents the excess of the purchase price and related costs over the fair value assigned to the net identifiable assets of a business acquired. We test goodwill for impairment on a quantitative basis at the reporting unit level on an annual basis or upon the occurrence of events that may indicate possible impairment. The test resulted in no impairment in the periods presented.

During the seven months ended December 31, 2013, and in connection with its change in fiscal year-end, the Company changed the date of its annual impairment testing for goodwill from November 30 to October 31. This represents a change in the method of applying an accounting principle. Management believes this change in the method of applying an accounting principle is preferable, as the earlier date better coincides with our annual budgeting and five-year planning processes. Management also believes that the change in our annual goodwill impairment testing date did not delay, accelerate or avoid a goodwill impairment charge. A letter from our independent registered public accounting firm, to the effect that this change is to an alternative method which in such firm's judgment is preferable under the circumstances, has been filed as an exhibit to our transition period report on form 10-K for the seven-month period ended December 31, 2013.

The changes in the carrying amount of goodwill, by reporting unit, for the seven months ended December 31, 2013 and the years ended May 31, 2013 and 2012, are as follows:

As of December 31, 2013, $137.7 million of goodwill was tax deductible.

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