problem with rank and countif function

[mychi11]

I tried to use the formula
=IF($E2<>"IUI",RANK(C2,$C:$C,1)+COUNTIF($C$2:C2,C2)-1) to generate sequential number based on date without repetition.
This formula works well. However, when i add in new row, the formula in the last few row tends to change. For example =IF($E68<>"IUI",RANK(C68,$C:$C,1)+COUNTIF($C$2:C69,C68)-1).
Is there anyway to improve the formula?

 

[jasonb75]

Sorry I don't have much knowledge in writing these formulas.

Everybody had to start somewhere. Many experienced users still refer to google, etc for things. There is so much to excel that it would be near impossible to remember everything.

I had to do a quick check on the syntax for the [[#Headers],[Column]] part and I still missed the comma