Restrict KPI from changing when filters are applied

[Fsosa11]

HI  Guys, I'm having some issues with KPI values remaining the same while a filter is applied.

Firstly , I want this value not to change no matter which filter is applied : 
Count( {1}{<[EOL Year] = {">=2021"}>} Camera_Model ) / Count({1} Camera_Model )
   **The value does not change when EOL Year is applied but does change and Region is applied, I would like the value to stay the same if region and/or Eol Year filter is applied **

Secondly , I want this KPI to only show a value when the fields EOL or Region is applied: 
count([Camera_Model])/count({1}[Camera_Model])
**When no selection is made, the value displays 100% but i would like the KPI to display no value, or even better,  not even appear on the board unless EOL Year  or Region is selected **

I tried multiple set analysis scenarios and have not found a result, any help is greatly appreciated 

[MayilVahanan]

HI

Try like below

1. Count({1<[EOL Year] = {">=2021"}>} Camera_Model ) / Count({1} Camera_Model )

2. If(GetselectedCount([EOL Year]) > 0 or GetselectedCount(Region) > 0, 

count([Camera_Model])/count({1}[Camera_Model]), ' ')

[Fsosa11]

Thank you Sir but none of the proposed solutions worked.  How ever i did find that fx 
if(GetFieldSelections([Region])&([EOL Year]&([Site]))>0,$(vCameraTotal),'') displayed a value only if Region or EOL is selected which is exactly what i wanted.

Now I'm having difficulty with fx 

Count( {1}{<[EOL Year] = {">=2021"}>} Camera_Model ) / Count({1} Camera_Model )

displaying  a fixed value no matter what is selected