I copied some data down to excel from the internet (no .xls or .csv
download available, just a straight copy and paste, unfortunately).
The data is in the format below:

5,503,522 7,268,551

There is a space between the numbers. I have used right, left, find
and len formulas in the past to separate text like this, but I'm having
trouble with this one.

Assuming the above data was in cell A1, I initially tried using the
formula

=RIGHT(A1,FIND(" ",A1))

However, this returns 551. I checked this and running FIND(" ",A1)
returns a value of 3. This doesn't make sense to me either, but if
anyone could explain a solution or why the FIND formula I was using was
returning that particular value, I would appreciate it.

Thanks.