Hi, I want to combine columns of data into one, e.g.
to combine column 1, 2 and 3 into column 4 (excel prof. edition 2003)

column 1 column 2 column 3 column 4
1 a i 1
2 b ii a
3 c iii i
4 d iv 2
5 e v b
6 f vi ii
7 g vii 3
....

Thanks in advance.