Re: Dell's 1Q performance based on a re-swizziling of fiscal calendar
That's a fair question. Sellers are typically motivated to drive hard in the last month of their year to meet quotas. The last month of the most recent year was January 2018 (one year after the change you accurately mentioned).
IDC's most recent report covers the calendar year for all vendors for Jan-March 2018. (It takes them a little over two months to assemble that data and report on 1Q18. The large change is compared to EMC's 1Q17 calendar performance, which was the first quarter of their 2017 fiscal calendar, meaning the lightest quarter of the year for most sellers.
So compare really heavy month activity to really light months and you get a large delta swing.
Hope that helps.