**Breaking: Trump craters to 40% in new Ipsos Poll as Democrats surge to 46-34 Congresional lead**

[regnaD kciN]

7. I'm confused as to how 538 is evaluating that poll...

...since, if you click on the link next to it, it shows a quite different picture. They list the rolling average between August 21-27 as 40% approval, but, by the graph itself, it would indicate the rolling average as of the 27th was 38.1% approval, while indicating it's a rolling total, not just that day's portion thereof.

The main issue here is "craters" -- one might say that, since Trump's approval rating has remained a couple of points on either side of 40% practically since he took office, any variance is less a matter of "cratering" and more the standard MoE at play. However, if you look at Ipsos' own graph, you see a very noticeable movement over the past week over approval/disapproval.

8/20 42.9 52.5
8/21 42.1 54.1
8/22 40.4 54.3
8/23 39.1 55.5
8/24 38.6 55.9
8/25 38.7 55.6
8/26 38.3 55.9
8/27 38.1 55.9

Looking at those numbers, there's little statistical "noise" to be seen, just a steady drop, from a disapproval margin of +9.6% to +17.8 over the course of last week. Does that mean that Trump can't rebound? No. But it does mean that the events of last week seem to have had a definite effect that can't be explained away as simple random drift.