For fiscal years that end between Jan. 1 and May 31, Morninstar assigns the previous calendar year as the date of the fiscal year. This is because the bulk of the financial activity occurred in the previous calendar year.
For example, McKesson Corporation's fiscal year ends at the end of March.
As of 12/2/2016, their last fiscal year end date was 3/31/2016. The annual data shows the last fiscal year to be 2015.