I am developing a simple app and this app requires keeping track of previous
value entered into a cell before dragging new value on it.

I have an external source from which I dragdrop values into excel cell; but
some cells on my excel sheet already contains data - so I want to append this
new dragged data to my previously existing data on that cell. Which event on
excel should I use to keep track of it?

Currently I am using Workbook_SheetChange event to do this; but when I
dragdrop data on a particular cell that already contains data;
range.cells.value2 in workbook_sheetchange or workbook_SheetSelectionChange
events are giving me the dragged data and overwriting previous existing data
on that cell. How to resolve this issue?

Any help is really appreciated!!

Thank You!!