Several questions. Lets say I have a column designated for order numbers. Its in the format of XXXXX-YY.

Example:

Row 1 40200-14
Row 2 40201-01
Row 3 40202-08
Row 4 40203-55

Notice how the number before the dash increments by one.

So my questions are:

1. Is there a way I can have Excel automatically increment the number before the dash every time someone enters a new row?
Example: If I enter 40209-10 then next row I enter would autofill 40210.

2. Is there an edit I can put in that will only allow numbers that are higher than the previous number entered?
Example: If I enter 40298 on the last line, what can I do to ensure I don't accidentally enter a lower number such as 40198? (I actually did that today).

Any information would be appreciated. Thanks.