How do I set dual units (SI and FPS) on a chart

[Zakaria]

I like to show the SI unit of left of y-axis and FPS unit on right of y-axis

 

[Jon Peltier]

I would set up a dummy axis like this, with a customized FPS scale linked to
the SI scale:

http://peltiertech.com/Excel/Charts/ArbitraryAxis.html

- Jon