I think what he means is that the proportion of shares is similar in each round, but the payment is different. I think your prop fee is 3%, so:
6041 / 19191553 * 25 * 0.97 = 0.007633267, was paid only 0.00361762
340 / 1080488 * 25 * 0.97 = 0.007630811
2355 / 7643323 * 25 * 0.97 = 0.007471717
Oh, sorry, didn't read this carefully enough.
Then maybe he temporarily switched some of his miners to PPS mode ? PPS reward is not shown in this table.