DATEDIFF calculation error

OK, good news!  DateDiff doesn't freak out over Nulls, it just returns another Null.  (See screen shot 3).  It also has no issues with days equal to each other... (Sorry for those wrong paths).   (also screen shot 3).  

This is my formula if you want NULLS to pass thru for no End Date.  (Best practics)

DateDiff2 = IF(Table1[Start_Date]<=Table1[End_Date],DATEDIFF(Table1[Start_Date],Table1[End_Date],DAY),(DATEDIFF(Table1[End_Date],Table1[Start_Date],DAY)*-1))

This is another option if you want 0 instead of NULL for a null end date.  

DateDiff2 = IF(ISBLANK(Table1[End_Date]),0,IF(Table1[Start_Date]<=Table1[End_Date],DATEDIFF(Table1[Start_Date],Table1[End_Date],DAY),(DATEDIFF(Table1[End_Date],Table1[Start_Date],DAY)*-1)))

See if this works and sort the result ascending... i'm curious what PowerBI is seeing that's still making it think the dates are reveresed...  (Please let me know, I'm sucked into the mystery now...)

FOrrest