Here's the understanding proccess, but at the end there's a single formula, you can jump to it if you like.
First you make a column containing the position of the separator (that's the point symbol ".")
Supposing your numbers are in the A column:
B1 = find("."; A1)
B2 = find("."; A2)
...
At the end of this column, let's say B20, you put the maximum value of the point position:
B20 = max(B1:B19)
Now, let's calculate how much spaces you need for each number.
That's the difference between max point position and current point position:
C1 = $B$20 - B1
C2 = $B$20 - B2
...
And finally, add that spaces.
Here's an important thing: use a equally spaced font, like "Lucida Console".
D1 = rept(" "; C1) & A1
D2 = rept(" "; C2) & A2
...
Of course you can try to get it all together in a single formula, but I tried to let it well explained. You could, for example, take a fixed max point position, say 10, and do:
= rept(" "; 10 - find("."; A1)) & A1