First, many so-called toggles are in the form of a checkbox, and their descriptive text is only for "show," "display," "enable," or any other such positive action, when the control is selected.
The descriptive text of a checkbox doesn't describe the opposite effect occurring when it is deselected, so there is no reason to do so here either.
Since the slider that lets you select the year will also describe a date range, there is no reason to add that to the text that comes before it.
I will also echo some of the comments that say to use time period; however, that can be used as the label for the slider control.
The following is a shortened, but still understandable, version of the controls and descriptive text:
- [x] Show candidate unemployment. Time periodcandidates who were unemployed (Nono selection.).
- [x] Show candidate unemployment. Time periodcandidates who were unemployed (2018–2020).