Dazed and confused
'Course CONSUMER sales of PC's are down. Welcome to 2018 : Why would Auntie want to fire up a box next to and the size of a microwave to check her recipe for [black]/[bread] pudding? Why would Grannie want to struggle with a box next to and the size of a dishwasher to email little Johnnie and Joanie? All done on a phone, not even, or seldom, on a notebook.
What would be a lot more interesting and relevant is sales to companies.
Come to think of it what would be even more interesting is, given the ubiquity and multi-functional abilities of the desktop PC, how as a direct result the labour market for a given GDP has shrunk in 20 years.
I am going to stick my neck out here and say that 5 low- to medium-level jobs of a routine or clerical nature of 20 or 25 years ago should now be capable of being done by one person (trained, natch) and a desktop.
And even (it's OK I am going to stop soon) whole departments in larger companies such as internal mail delivery ought to have been mothballed by now.