Neglecting the fact that you're comparing ice core samples to actual atmospheric measurements (which is apples and oranges) that's a great bit whopping change of, drum roll please....

.007% OMG

Any boob with Excel can make a hockey stick looking chart as long as you get to make up a 'y' axis...

What about Arkh's 500 million year graph, showing 3 or 4 different models that all indicate a drastic decline over the last 100 million or so? Does his mean less than yours?

[Linked Image from i30.photobucket.com]