If you have a wideband O2 sensor fitted then this table lets you specify what AFR (Air Fuel Ratio) targets StayTuned will use.
So with this table you’ll notice the values at the top/left (idle/no load) are leaner with values around 13-14 because you’re more interested in efficiency at that point (higher is leaner) but as you get to the bottom right (full throttle) they’re getting richer and more in the 12-13 range (lower is richer) since that’s when you want power.
The PCV has a similar table and there I normally ran around 13.7 across the board which gives a nice responsive ride and then more like 12.6 in the bottom right corner (e.g. over 80% TPS and over 8k RPM) since then you’ve got it pinned and want all the power it can summon.