SKIPREC and STOPAFT in Sort Cards

These are quite easy, but even then i went wrong a few days back so thought of putting it here

SORT FIELDS=COPY,
SKIPREC=1000
Now here in the output file the initial 1000 records are skipped.

SORT FIELDS=COPY,
STOPAFT=5000
This copies the first 5000 records in the output file and then the processing is stopped

Now, when we club both-
SORT FIELDS=COPY,
SKIPREC=1000,
STOPAFT=5000
Here first 1000 records are skipped, then from 1001 - 6000th records are written to output file.
But I was under the impression that only 4000 records will be written and hence i went wrong..