The formula is valid for E+/-999, if you have a number beyond this increase the number of the last three zeros, and change the second 4 to the number of zeros +1.
You can then add another label, as desired, that indicates the values are expressed in thousands. Only the thousands portion of the values in the axis should be displayed.
That way, instead of 20,000, 40,000, 60,000, and 80,000, you would see 20, 40, 60, and 80 along the axis. Determine the number of significant figures associated with a given number. For instance, if the values along an axis ranged from 0 to 80,000, you may want to have only the thousands portion of each value displayed on the axis. It is very common for charts to use some sort of "shorthand" for values placed along an axis.