How to set View height as percentage of the screen height in Storyboards with XCode 7

Basically you need to act on the multiplier property of an height equal constraint. To do that while pressing CTRL, drag from the view to its superview and select equal heights constraint, later edit this constraint in Size Inspector by setting its multiplier the desired value can be expressed also as 1:25, 1/25, 0,025. If it working on the contrary just reverse items as in the picture.