Answer :
You have said that he used 180 in the first two weeks.
That left him with 200 at the end of the first two weeks.
Then you said that he had 2 left after another 2 weeks.
So during those 2 weeks, he used (200 - 2) = 198 in the 2nd 2 weeks.
What we all expected has not happened at all: Frank is not slowing down !
But, even so, we have to ask ourselves just what Frank is doing with them all.
Nobody can blame you for wondering.
I think it might be 198 because it has after the 2nd week he has 200 left and if he has 2 on the 4th week he uses 198 tell me if it was useful