iWork Numbers increase column size for sum If I have columns that sum at the bottom, how can I have the sum function automatically include a newly inserted row.

    a
  +---+
1 | 1 |
2 | 1 |
3 | 1 |
4 | 1 |
  +---+
  |=sum(a1:a4)|


Then when I add row 5 the sum function should be

=sum(a1:a5)
This functionality is embedded and its default behaviour. Of course if adding a row will be done using this option: