Filtering based on relative date

I'm trying to filter records for the last three years of data but want to avoid having to edit the transformer on a yearly basis (ie. TestFilter: Year= 2021, Year= 2020, Year = 2019 - necessitating a yearly update at the change of the year). I'm hoping to find a way to set up an attribute filter or test filter that can be set on the relative time frame (ie. Year = this year, Year = last year, Year = two years ago). I'm guessing there is a simple way to do this with the text editor but I haven't been able to figure it out!