All the officials so far:
http://www.bbspy.co.uk/cbb18/ratings/official
Every single official has been higher than last summers officials.
And for overnights, there was a small dip mid week last week as the Olympics was coming to it's conclusion... those same 3 days on CBB16 happened to be higher than usual (Farrah and Jenna returning from the secret house), but in fact AFTER James and Lewis went this weekend, ratings picked up again:
This is the overnights on CBB16:
http://www.bbspy.co.uk/cbb16/ratings/overnight
And CBB18 overnights:
http://www.bbspy.co.uk/cbb18/ratings/overnight
As you can see there was a dip last week, but the table for CBB18 hasn't updated since Friday.... but Friday's eviction got 1.6m compared to last years 1.3m, Saturday got 860k compared to last years 820k, and Sunday shows both got 1.5m.
So please read the ratings before believing articles.