Lead Scoring Report

Okay, so when you use the Score was Changed filter with a new score range, Marketo will pull up everyone who has a change score activity with the new score value within the specified range, and not the people whose current score or the final score in the month of your interest was that value. Also, the person score values that you see in the report are their current Person Score values, as I said the Score was Changed filter looks for activity in the activity log, and not just their latest or last score change activity in the month. Don’t you have an RCM model tied to your scoring model that updates the person’s stage when they hit the respective stage’s scoring thresholds, e.g., Change Revenue Stage to MQL when their person score is 80 and they meet the rest of the criteria to be an MQL lead? I think using the Revenue Stage change activity filter would be much better and cleaner and more accurate than using the score change activity filter. You can also use the People By Revenue stage report that allows you to Group people by their revenue stage.

Similar to what Darshil suggested, I would recommend updating your report to group people by their lifecycle stage or status rather than the score by tens, then in the smart list for your report, also indicate that a person's score has changed in the last 30 days to reduce all those zeros. The smart lists you're using for custom columns are not going to filter the entire report as well so you'll just need to make sure that's accounted for in the smart list of the report. 

Hope that helps!