Camera momentum after lifting finger

Hi there! I was looking to see if anyone could help me figure out how I would implement camera momentum after the finger is released. I can move the camera from left to right with bounds on both sides. How can I figure out how much momentum to add to the camera after a swipe with the finger. (Kind of like Angry birds). The faster the swipe the more momentum I think?

I tried

Input.GetTouch(0).deltaPosition / Input.GetTouch(0).deltaTime;

It makes my camera jump to far.

Thanks for any help you can give!