Overall approval of President Bush's job as president, through 9/13
Five polls have come in since the last update, so time to take another look at approval of President Bush, and the post-Katrina effect.
Gallup, Pew/PSRA and ABC/WashingtonPost were all in the field 9/8-11. The approval ratings are Gallup 46%, Pew 40% and ABC/WP 42%. That is unchanged for Pew since their 9/6-7 poll, and down 3 points from 45% approval in ABC/WP of 8/25-28, just before Katrina made landfall. Gallup, on the other hand, shows a 1% gain in approval from 8/28-30, partially after landfall but before the magnitude of the disaster was clear. See MysteryPollster.Com here for comments on the general downward trend in polls between July and now, along with a familiar looking graph.
The two latest polls are NBC/WSJ/Hart-MacInturff 9/9-12 and CBS/New York Times, 9/9-13, at 40% and 41% approval respectively. For NBC/WSJ that is a drop of 6%, from 46% in an elderly poll taken 7/8-11. For CBS/NYT the change is a drop of 1% from the CBS poll of 9/6-7.
So four of the five polls show declines, but from different baselines at different distance back in time.
We now have 14 post-Katrina polls for estimation. My analysis suggests an effect of Katrina of about -1%, once the negative trend since January and the effect of polling organization are taken into account. That estimate barely fails to reach statistical significance. The fact that 12 of the 14 post-Katrina polls fall below the simple trend line in the figure above, makes it clear that Katrina almost certainly has damaged President Bush's approval rating, but the effect does not appear especially large. The president has been losing .03% approval each DAY since January, in my model across all polling houses. That amounts to about 1% loss per month, or close to 8% since January. That the post-Katrina polls suggest a -1% impact amounts to an additional "month's" worth of lost support due to Katrina.
