Adding exactly 1 month to initial date

Hi all,

I have a date on the top left hand corner of my excel sheet. I want to add exactly one month to that date in a vertical list (without using micros please) any ideas?

Example:

1/4/2005
1/5/2005
1/6/2005
1/7/2005
1/8/2005
.
.
etc


PS: I tried adding 30 (or a similar number like 29). It works but not if I want a large list of dates, which is what I want. The reason why it doesn't work is, I hope, obvious.