If you decline 17 points from (say) 75 percent, that's a decline of more than twenty percent within two months. So, how are similar drops over comparable reported? When (for example) stock markets lose over twenty percent of their value within a couple of months, do financial publications religiously refrain from using the word "plunge"?

But I don't imagine that hacks like Kaus ever invest five seconds asking themselves such questions.

In fairness to Kaus, the FOX News/Opinion Dynamics numbers [which are pretty typical, despite the sponsor] show Bush's approval rating dropping from 68% on Nov. 19-20 to 59% on Jan. 29-30 -- a 9 point decline. [Early hints are that the State of the Union address didn't make much difference, but it's too soon to be sure.] So, by "swing" Kaus may have meant the change in "net approval" (approval minus disapproval). And a drop from the high 60s to the high 50s isn't necessarily a "plunge" -- although, as a rate of change over about 11 weeks, I can't insist that it _isn't_ a plunge. (That figure does include a bit of a post-election spike; the decline since late November looks to be around 5 or 6 points, as in Brad's recalculation of Andrew Sullivan's numbers.)

Basically, my impression is that Bush has returned to normal politics. Presidential approval usually runs between 40% and 70%, but Bush sailed in the 70s and 80s for a while because the Democrats weren't pushing him very hard. Now that the political discourse is returning to some sort of "normal," the approval ratings are, too. [Bush's approval was around 55% before the September 11 attacks.] Extending Jeffrey Kramer's argument, if the 'normal' range of variation is 30 points (between 40% and 70%), then a drop from 68% to 59% in a few months can't make Bush's political folks very happy.