If you use one column of your data to contain the row number of each
row, you can use the Subtotal function to identify which row is
visible.
Assuming row 1 is always visible and contains your column headings,
and
assuming column A contains your row numbers.
Use the formula =Subtotal(9,$A$2:$A$60000). This returns the sum of
the visible
cells in column A.
Since only one row is visible at a time, the sum of the visible cells
will
be your row number.
You can also use Subtotal to identify up to two additional visible
rows.
=Subtotal(4,$A$2:$A$60000) will tell you the maximum visible value in
column A, i.e. the last visible row number.
=Subtotal(5,$A$2:$A$60000) will tell you the minimum visible value in
column A, i.e. the top visible row number.
If there are three visible rows, =Subtotal(9,$A$2:$A$60000) -
Subtotal(4,$A$2:$A$60000) - Subtotal(5,$A$2:$A$60000) will tell you the
row number of the second of the three rows.