Two Bone IK Bones Space

Hello everyone, help a newbie. In the Two Bone IK node settings, I chose Bones Space.

Then I manually changed the position of the foot and the Effector Location values automatically changed.

My question is how to calculate these values if, for example, I want to lift my foot up by 10? What is the formula for calculation? Where can I read about it? This will be similar to how the Leg IK node works.