Part of the slight decline is due to variance as I assume you all are familiar with. Factors like food, amount of sleep, general fatigue, temperature in the room, etc.
In this particular case I did some 3 for 1 "jump-up and hold, go down slowly" pull-ups after I was wiped out on regular ones. I haven't done those in a while and had been sticking with just body rows, which are significantly easier. So I think I got a better arm workout in this case.
I'm having trouble with squat form. Hands on hips? How far down? How do you both stop your knees from crossing over your feet and keep your torso relatively upright?