Difference in Dates Calculation

Hello -

See the attached .xls.

I would like assistance in calculating the difference in calendar days for two scenario's:

TT Credit Date 1 (Column D):
Subtract Column A (Ship Date 1) - Column C (Credit Date); output the expected value in Column D ('TT Credit Date 1')
- If 'Credit Date' has a date prior to 'Ship Date 1', output a '-1' in Column D.
- If 'Ship Date 1' OR 'Credit Date' are blank, output a '-2' in Column D.

TT Credit Date 1 (Column E):
Subtract Column B (Ship Date 2) - Column C (Credit Date); output the expected value in Column E ('TT Credit Date E')
- If 'Credit Date' has a date prior to 'Ship Date 2', output a '-1' in Column E.
- If 'Ship Date 2' OR 'Credit Date' are blank, output a '-2' in Column E.

Thanks!

This

If 'Credit Date' has a date prior to 'Ship Date 1', output a '-1' in Column D.

Seems to be a condtradiction to the original subraction

Subtract Column A (Ship Date 1) - Column C (Credit Date)

Do you perhaps have that backwards ?
Going by your manual entries in D2:D4, I think you meant if A is prior to C then -1.
Same for Scenario 2

Try this in D2 and filled right/down
=IF(OR(A2="",$C2=""),-2,MAX(-1,A2-$C2))