I'm using Excel 2003. I have a file with columns as below:
(below diagram, the cells are separated with '|' and '-')
_|_A__|__B__|__C__|__D__|
1| 1-Jan | A,B,C | 1-Feb|C,D|
-----------------------------------------
2|2-Jan | B,D | 2-Feb|C,D,E|
-----------------------------------------
3| 3-Jan...