How to use a loop to increase a scroll view size (swift3)

Right now every time the button is pressed a the score goes up. Once the score hits 3 the scrollviews height is increased. How can I make this so every time the button is pressed the height increases by 50 for a infinite amount of times.

@IBAction func enterScore(_ sender: Any) {
        score += 1


            THESCROOL.contentSize.height = 1000
            if score >= 3 {
                THESCROOL.contentSize.height = 5000

            }}