चलती है (ग्वालियर-भोपाल वाया गुना बीना ICE) उड़ती है धूल जलते है दुश्मन खिलते है फूल - Adi Singh

My one question to the #Admins/ #Moderator
At the Right side of the window there is the section 'Top Img Train'. There all the trains have been rated like One Star, Two Star, Three Star in this fashion.
Can you please tell me how that rating is calculated?
Thanks in advance.

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