Total number of days from two different dates

[IPDaily]

G'day,

I wish to calculate the total number of days from a given date to todays date, simple you say, however, the reference date can be from one of two cells in "D" & or "E".
Any one of the two cells can be empty, any one of the two cells can contain a value, both can be empty at the same time, both can contain different dates at the same time.
The priority when both cells contain dates is to return the total number of days from cell "E" to todays date.
If only one of the two cells "D" or "E" have a date, I need the number of days, the difference to todays date referenced in cell "F".
If the both "D" & "E" cells are empty. I would like cell "F" to be blank (currently with the formula below I get 44819).
=IF(E75<1,TODAY()-D75, IF(E75>1,TODAY()-E75))

Note: cannot have a macro.

 

[bebo021999]

In F5 drag down:

=IF(AND(D5="",E5=""),"",TODAY()-IF(E5="",D5,E5))

 

[Peter_SSs]

.. or simplifying that slightly

=IF(D5&E5="","",TODAY()-IF(E5,E5,D5))

 

[IPDaily]

In F5 drag down:

=IF(AND(D5="",E5=""),"",TODAY()-IF(E5="",D5,E5))

Thank you very much.