Thank you for the opportunity to help you with your question!
Case Study: Take three companies coefficient variations
Safaricom = 0.377737064
Airtel = 0.56783
Orange = 0.44331523
The lower the coefficient variance the less volatile the returns. Orange offers the lowest return of all three, at a variance higher than Safaricom. this therefore warrants removing it from your thoughts. Airtel offers returns double those of Safaricom but at variance less than double that of Safaricom. Therefore my vote goes to Airtel
Please let me know if you need any clarification. I'm always happy to answer your questions.