Inverted Scroll Rubberbanding

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    for (i, view) in scrollView.subviews.enumerated() {
        var ty = 0.0
        if scrollView.contentOffset.y < 0 {
            // We're scrolling past the top of the scroll view.
            // Translate each item in the scroll view by some amount based on its index and scroll offset.
            ty = CGFloat(i) * abs(offsetY) / 8.0 * pow(1.12, CGFloat(i))
        }
        view.transform = CGAffineTransform(translationX: 0, y: ty)
    }
}