Apple Sells Only 4.1M Macs In Q1 2013, Down 21% Yearly And 16% From Previous Q

Am I correct in thinking that all things being equal, when a quarter is shortened by a week, we'd be accounting for an automatic 8% less. 12 weeks in a quarter, only accounting for 11 this time around.

With the other factors mentioned in the article, is it safe to say Apple is about even with 2012?

Steve Jobs said himself that we're entering the post PC era.

Apple has fared pretty well despite this fact but it may be affecting the company now.

Not too big a concern though. Using Steve's own car/truck analogy it's like reading too much into why cars sell more than freight trucks.