03-24-2015 11:23 AM
Proc export doesn't really have that option unless you want to create a new sheet. You can update exisiting Excel workbooks by use of libname see:
However it depends on what you want to do. What is in the existing spreadsheet, is it tabular format or all mixed up. You may find that its easier to export any data from SAS to CSV, then in your workbook write a VBA macro to import that data and process it into your file. Remember, SAS deals with fixed structure datasets, much like a database. Excel does not, it allows anything. Therefore the two are not necessarily useable from the other.