WordXP

I created the pivot table successfully and am up to dragging the field and
putting them in the column.

Why is it that sometimes I put the field in the column and it fills out the
entire column with the info (ex. putting the "serial #" field in the column
produces all the serial numbers to show up in each cell underneath) and
other times I put the field in the column and all it shows is the sum
amount.

What is happening?

Thank you.