How do you change the navigation system from kilometers to yards?

I have the new 5th generation navi in my rx350. I never tried to change it to yards but a suggestion is: at the bottom of your screen you will see a + and a - symbol on each end of the screen. My only suggestion is to slide between the two and see how close you can get to yards. I doubt it will bring you that close however, but it's worth a try.I would like to know myself if anyone else can offer any suggestions.