In first place, you could make a Variable with avg (Total Age), this will improve the calculation time, because it calculates only one time, not for every bubble.
In this case, I will name the variable as vAgeAvg (its contents is =Avg(Total Age).
In Color expression, you could try:
If(PMPM>=2500, red(), green()),
if(PMPM>=2500, blue(), Yellow())
If it isnt the answer you need, please, send a reduced copy for better understanding.
I added your code, but now all the dots are being colored yellow because it's the else option in the if statements.
I can't add the extra expression to calculate the avg(Total Age) because it doesn't give me the option to make it invisible.
Age and PMPM Example.qvw 199.0 K