Is Water Spout based on the numerical amount of HP or the percentage of HP?

Question

Water Spout the move with 150 Power, and based upon your HP.
But is it percentage or the actual amount?
50% or 200/400 HP?

Answer 1

Percentage.

If it was amount wailord would beast though..
But yep, its percentage.

For example with 50% HP the power is 75, because 50% of 150 is 75.