Query Builder - finding.firstFound

I’m in quite a problem here. I’m looking to find the total number of unique vulnerabilities that are net new over a period of different timeframes. It seems the the finding.firstFound ignores any “older” findings of a vulnerability when I select “between” date ranges.

For example, if I do finding.firstFound BETWEEN 2021-01-01 AND 2021-01-31 I find about 440 vulnerabilities. So to check that this is true, I looked into one of the vulnerabilities listed to make sure that the vulnerability was not found in the environment prior to this date range.

In this range, I found vulnerability.title = ‘Adobe Flash Player Obsolete Version’ was first found on January 17 2021. I then looked up vulnerability.title = ‘Adobe Flash Player Obsolete Version’ and found that the first time it was ever found (taking out the date range) was actually March of 2017.

Is there any query builder logic that could be implemented to show me the unique net new vulnerabilities per date range? I don’t really care if one asset shows a vulnerability as “first found” if the vulnerability is not new to the environment. I can’t seem to find a dashboard card to helps show these statistics either.