The Gold Nitro targeting report in your dashboard shows each of your targeting hashtags and how many followers they brought you. The rate column shows the quantity of actions we took (likes or follows) divided by the number of followers gained, as a percentage. The timeframe is the last 7 days, a trailing week.
In the example below, #nature brought 59 followers in the past week and converted at 5.8%. These conversion percentages will always be low, since it takes a lot of actions to gain followers.
To improve your follower gain, each week or so remove hashtags or other targets that are underperforming, not bringing you many followers. In the example below, we should remove #mountains because it's not bringing us followers.
Underperforming hashtag targets usually have a low volume of posts. Underperforming account targets can be because followers of those accounts don't like your content, or because we've already exhausted all the target accounts followers.
You can read more about targeting in these articles: