format cell data to display stacked data

[Guest]

How do I format a cell to display two stacked numerical values?

 

[Max]

Not sure whether you're referring to this ..

Pressing ALT+ENTER will break for a new line inside the cell

So you could try, say in A1:

Type "100", press ALT+ENTER, type "200", press ENTER

Then it'll appear in A1 as:
(but as "text", not numbers)

100
200