I'm sorry, but how is this so hard for you to understand...?
PS3 was at 80M as of November 2nd 2013, NOT as of December 31st!. I know this comes from Sony's own statement, but this was released on November 6th 2013. That does not include end of year results. So Sony didn't skip any months. You are doing it and whoever did the Wikipedia entry and seemingly don't understand it.
1. 3.4M 2014 sales don't include any sales from 2013
2. 80M up to November 2nd 2013, doesn't include any sales after November 2 2013.
still following me?
And therefore adding 3.4M and 80M does not give you sales at the end of 2014.
Sony released the end of year 2013 results only in February 2014 and at that time they didn't separate PS3 and PS4, those combined did 7.8M units.
Later on Sony started to separate the numbers again and also reactively to a degree. That's why we know that PS3 did 3.3M units in calendar Q4 2013
But how many of those were sold prior or after November 2nd is anyone's guess. It's fair to guess that quite a few of them were shipped after the cutout point though, so therefore the actual PS3 shipped figure at the end of 2014 is quite a bit more than the 83.4M you tossed around. I'd guess at least 2M more.