We could use officers to illustrate what I am trying to explain (although for Paul's purposes this is not the correct category of men).
If we have the 41 officers present and, in addition, say one was detached and one was in hospital in June, then the total roster strength of officers is 43.
Using your casualties there are 1 killed and 19 wounded for the total of 20 casualties. Let us assume all the wounds take the men to the hospital except for 8 who are wounded but can still serve
This moves the present for duty strength from 41 to 29, as you report (41 less 20 plus .
For Paul's purposes the total of 43 need only be adjusted for the one man that died, so the roster strength is 42 because all those detached and in the hospital are still part of the regiment.
So, again, thanks. - R