Necromantle Bone Raiment miscalculation

My Infernal Hound is currently Level 13 with 5568 Maximum Life.
Because the tooltip says "Minions gain 31% of their Maximum Life as Extra Maximum Energy Shield", I expected to get 1726 Energy Shield. Instead I only got 377 Energy Shield, which is about 6.77%.

Switching out Meat Shield changes Maximum Life, but not Maximum Energy Shield, which leads me to believe it's coming from BASE Maximum Life instead of the current value.

If this is intentional, please clarify that in the description.
If this is not intentional, please correct the calculation.