Largest 5 National Marketing Organizations - MedSup Sales

So, I'm compiling a list of largest Medicare supplement NMOs in the nation with the purpose of comparing the pros and cons of each.

So far, the list I have is:

Amerilife
Senior Market Sales (SMS)
Ritter
AIMC
Agent Pipeline

Who is missing from the list? Also, any idea of sales volume for each of these?

Thanks in advance.

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