When I copy a cell by dragging the cell contents to adjacent cells (clicking
on the bottom right hand corner of the source cell and dragging) I get one of
two responses; (1) it works, copying the cell contents to adjacent cells so
that the values in those adjacent cells are identical to the source cell or;
(2) the values in the adjacent cells are incremented, whether the source cell
is a number or a date.

How do I specify how I want the copy command to proceed? It seems to decide
on its own.