I might be a bit optimistic for PS4 this year since its been up YoY so many months. But last year had nothing going by the same logic. The top games were sports games and old games. This year we at least have Destiny 2 instead of Taken king or collection of Destiny. And LE bundles tend to just add to sales rather then replace sales.

Edit: Oh and 160k August last year became 191k this year. If we use the same % increase then we get 340k for PS4, but even I am not that optimistic. XB1 will definitely be down because it had a lot going for it last year and this year there is the XB1X.

PS4 had the slim model launch and a price drop to $299 in September 2016.

Did it help sales? IIRC the PS4 slim flopped. And even it it did help sales it was only available for half the month, which means the other half had mediocre August like sales. All the Septembers for PS4 with a new Destiny were superior to it.

Also this article makes it seem like the PS4 was already $299 or similar value. https://arstechnica.com/gaming/2016/09/ps4-slim-review-2/

PS4 dropped to $299 the week before the slim launch. 

The price drop/slim helped boost the weekly average over August by 42%. That's bigger than the 2015 boost, +36%.

Because it sucked sales out of August, and the numbers were pathetic so a large % increase is not surprising. The actual sales increase was lesser. Lets take another look

2014 Aug+ Sept: 190k+538k= 728k

2015:  209k+ 354k = 563k

2016: 160k+ 285k = 445k

2017: 190k + ??? = ???

If we take weekly avg of August and compare to September, September 2016 was almost equal to August 2015.

2014:  47.5 to 107.6

2015: 52.25 to 70.8

2016: 40 to 57

2017: 47.5 to ???

Ignoring Destiny month, 2 years in a row the PS4 increased by 17k/ w.  Leading to 64.5 * 5= 322.5k. But I am not that optimistic and personally predicted 310k,  which would be quite the disappointing month. Anything less than that would be ridiculously bad imo, of course it could still happen with the Switch effect but so far it hasn't been true.

No sales were sucked out of August since the slim and price drop were both announced the same week in September.

Okay then the numbers were simply pathetic. Do you happen to know PS4s bottom months? I would bet that August 2016 was one of them. And for 5 week months September 2016 was pretty bad. Clearly a bad time for PS4 sales, unlike now imo.