First time poster need help checking for changing value in Column data, then applying subsequent id from separate column

[rrrr0000]

Hi, thank you in advance for any help and apologies if this is poorly worded or already solved elsewhere. It is fairly specific so I couldn't find any previous threads on it.
- using Excel 2010, Windows 10

- I have a column A of data ("name") with changing values - many values are duplicates, and all ordered.
- I need to check for when the value changes in the col A "name", and when it does I need to copy a value from another column C ("sid") in order of data
- then take value from col C and copy it to a new column B ("sid_added") in order, to match when the value in COL A changes

This is what current data looks like:

name	sid_added	sid
Bob		1052
Bob		2002
Bob Green		2544
Bob Green		1542
Bob Green
Mary
Mary Orange
Mary Orange
Mary Orange

And this is what I am looking for as the end result:

name	sid_added	sid
Bob	1052	1052
Bob		2002
Bob Green	2002	2544
Bob Green		1542
Bob Green
Mary	2544
Mary Orange	1542
Mary Orange
Mary Orange

Thank you again for any help and time, it is much appreciated.

 

[Peter_SSs]

Welcome to the MrExcel board!

Is this what you want?

21 09 05.xlsm
	A	B	C
1	name	sid_added	sid
2	Bob	1052	1052
3	Bob		2002
4	Bob Green	2002	2544
5	Bob Green		1542
6	Bob Green
7	Mary	2544
8	Mary Orange	1542
9	Mary Orange
10	Mary Orange
sid_added

Cell Formulas
Range	Formula
B2:B10	B2	=IF(A2=A1,"",INDEX(C$2:C$5,COUNT(B$1:B1)+1))

 

[rrrr0000]

Thank you Peter, that is a very elegant solution and I think it solves my problem just fine

 

[Peter_SSs]

You're welcome. Thanks for the follow-up.