Don't think it can be done. However, if you need to know how many records a user has scroll thru, you could remove the scroll bar and use create 2 buttons (Previous and Next) to scroll, let say, the previous 10 or next 10 records. You need to write the nubmer of records scrolled to a file or a table. However, this does not seem to make sense, I mean, what if the user scroll forward 20 and scroll backward 7...
Anyway, good luck.