All you fellows were onto it immediately! I'm just getting back into this 'improvement' project now ( the urgent projects always win out, don't they?). And while it was difficult to find where to change the property (pull up the table, in the far upper left change view to Design, from the list that appears, click on field in question, a box appears below, then in the lower box, change the field property titled "field size" at the bottom, to double.
THANKS. I would never have known, or found it, otherwise.