On the Rank Tracker > Tags page, currently there isn't a way to see how many keywords are assigned to a tag. Therefore, context is lacking in relation to the remaining stats (e.g. a 100% increase could simply mean that 1 keyword has performed well if that tag just had 1 keyword)

Therefore, could you please consider adding a new column "Number of keywords" and display how many keywords are currently active within that tag for the data range selected.

Accounting for changes during that date range:

I appreciate there may be a challenge of what to do if tags have been added/removed during a period (e.g during the last 30 days, 90 days, etc). Therefore, one approach could be to in the number of keywords as a min/max value such as "10/15" which means during that date range, there have been a min of 10 keywords and a max of 15.

Related development suggestions:

Whilst checking if this item had already been requested, I couldn't see any asking for this exact functionality, but I did see this request for elsewhere in Ahrefs, so have linked to this task for your convenience: