I'd use an extra column and convert all the numbers to text (and no change to
the text values).

If your data is A1:Axx, then insert a new column B and
=a1&""
drag down

And sort your range based on column B.

Erin wrote:

I have pasted an example of the numbers below. Why does the sorting start
over at the bottom of the list? I want the last number on the list
87200.028.1 to appear after the fourth number 87200.028 and then 87200.029
would be after 87200.028.1

I realize that this is directly related to the faxt that the first numbers
have one decimal and the ones at the bottom of the list have two decimals.
What can I do about it?

87200.022
87200.023
87200.027
87200.028
87200.029
87200.031
87200.031
87200.032
87200.032
87200.033
87200.034
87200.035
87200.035
87200.036
87200.037
85600.403.1
86100.708.1
86500.403.2
87200.028.1

--

Dave Peterson