Overall % Change to a selected Date

Hello Bendlin, 

I have tried this equation but did not yield the subraction that we need. I was looking what is the problem but seems it is not reading the min date value when we click on the visual.

When I cick on a particular point on the line visual, It is giving me the date, I clicked on and not 2017 the min date. In this condition, giving me the subraction as "0" and not for example 120 -100 = 20 as a numerator. Not sure what we need to adjust in the min date dax. The rest of equation is correct.

What do you think?