Apple vs. PC Shipments: ‘PC’ Decline Worse Than Reported

Tom Reestman on numbers from Gartner and IDC that show "PC" sales slipping but Mac sales growing:

It makes sense until you realize Apple's (i.e., Mac) data is included in the same total to which it's being compared. In other words, Apple's stellar year is propping up the "PC" (i.e., non-Mac) numbers, making "PC" shipments look better than they really were. If you truly want to know how Apple did in the US on its own against "PCs", you must subtract it from the latter's numbers. […]

The originally reported dismal "PC" growth of -5.9% becomes an even more dismal -8.5% without Apple's numbers propping it up. That -2.6% delta is not insignificant, it's over 40% worse than what was reported.

via DaringFireball