Multiple Y-Axis Inputs - Single Filter!

Hi All. Hoping for some help on something that seems something that should be fairly simple to achieve but I can't seem to find the solution!

I have a visual that uses multiple column inputs from an Excel spreadsheet (Y-axis) and plots them against a month/year based timeline, 'Raised vs Solved: Smoothed' below: 

I want to be able to filter anything away that is less than a given number, say 2, across ALL y-axis inputs (in this case, the different names). The purpose of this is to show whether the different resources pools (people) are becoming too busy and at risk. 

The problem I run into is when I try to add a filter to each input, i.e. A. Barnes >= 2, it applies it across all inputs. As I happen to be < 2, it removes the other inputs too! See below:

How do I only apply the filter for A. Barnes to A. Barnes and not A. Barnes & J. Bloggs & J. Doe, etc? Or how do I apply a visual only filter when I have numerous Y-Axis inputs? Obviously the latter of these options would be ideal as I only have to update one filter instead of one for each input. 

I don't think I can use a page filter as I don't want to apply it to the other visuals on the page, i.e. 'Solved CCARs' or any other visual that I put on this page. 

Names removed to protect the guilty!

Any help would be greatfully recieved.