My colour vision is rubbish but it looks like it codes them High (>80") Low (<50") and medium (50-80). Medium is blue. I expect high and low are red and green. Or green and red. Or perhaps brown. Or ... who knows ... puce or something.
Now you know that, what do you know? Well, if you wanted to change the gearing on your bike, maybe you find yourself spinning out in top gear or dying the death on moderate hills in bottom gear, then now you know the absolute value for your hi and lo gears, and you can work out a gear combo that better suits your needs and put "what if" scenarios into the calculator.
Or perhaps you can work out that if I go x km/h in gear y then my cadence will be z. Or something like that.