Is there a way to get the elapsed time ratio of an animation outside of the state transition?

I have an animation state that transitions to another state when the user releases a button, but I want to be able to store how far into the animation the previous state got when the user released the button. Something similar to the “Time Remaining” nodes in the transition rules, but available outside of the transition rule, like in the Event Graph, when the transition starts. Is there a way to do this?