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Insert spaces within the call number stem and add a ^ symbol at the end of the call number stem to hold a space between the stem & remainder of call number:
Replace: M1.C422am with M 1 .C422am^
Create a new column called “949callno” and merge the two call number columns into the new one, using this formula: =(B2&C2)
Then copy/pull the formula in the first cell down the rest of the rows (Excel will translate the formula for each row).
The resulting column will display the merged call number, but will still contain the formulas underneath.
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To extract just the call number values, make another new column and copy the merged call number column:
Paste the data, as Values into the new column and name the new column: 949a.
Then erase all the old call number columns, leaving behind the new 949a.
Finally, Replace ^ with nothing and save.
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