Is there a way to measure if a lead score has increased by a given amount?

We just discovered that we have a large batch of leads in a "Recycle" stage whose lead scores were supposed to have been zeroed out but weren't. The Recycled leads are nurtured and when the scores come back up to the assigned threshold they become MQLs and are moved out of Recycle. Is there any way to create a smart list that measures how much a lead score has increased in a given time period. For example, what I want to know is if a lead's score has increased by 50 points from a certain date. Data value changed, lead score, new score is x, previous score was y, won't work because I don't know the previous score. I'd be grateful for any ideas.