Excel is not a good data transfer tool, you will find many problems with it. You have hit one of them. Excel can have a lot of properties/hidden things on cells. What is likely to have happened is someone has applied a format, or styling to all columns, therefore Excel assumes the working range is all columns. Thus when SAS imports the file, it checks the working area and imports all columns specified in the working range. To get round it, select the column aftet the last column of data, then select all rows to the right of that as well (CNTRL + Shift + Right arrow), then right click on that and select delete.
Alternatively, and far better (more robust, easy to re-produce, safer etc.) is to get the file in a proper data transfer file format, delimited file, XML etc. If you got a CSV, you would then write a datastep program which specified each variable to be read in, how its to be read in, what format/length, any other processing. Far more control and accuracy than some dodgy Excel file being read in by a guessing procedure.
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