Whenever there is a chance for a luck based effect to happen, the game rolls with the following formula:

P = B^((100-L)/100)

where

P = probability the event will occur B = Base chance L = Luck

This means that regardless of base chance, P approaches 100% as Luck approaches 100

Ghost Dodge Chance

When Ghost synergy is active, each Ghost Pokemon has a 15% base chance to dodge auto attacks. This translates to 17% more EHP against auto attacks.

With Luck Dice, a Ghost Pokemon withh have 26.5% dodge chance, or 36% more EHP. This is 16% more EHP than without dice.

At 63 you get 2x EHP.

At 78 you get 3x EHP.

At 85 you get 4x EHP.

At 88 you get 5x EHP.

At 90 you get 6x EHP.

At 92 you get 7x EHP.

At 93 you get 8x EHP.

At 94 you get 9x EHP.

At 95 you get 10x EHP, which is the cap.

So you don’t start getting much value from Luck at all until 60-90.