What is efficiency ratio of llobby to ground floor of high-rise mixed use condo?

[wagthedog]

Hi all,

I am not sure if this is the right place to post a question of this nature. I am touching up a feasibility assignment I did in my undergrad, one of the things that was missing was an ratio of lobby/common area to the entire ground floor of a high-rise condo with retail at-grade. Is there a industry standard, akin to an efficiency ratio of a entire building.

I have been looking on the internets to no avail. Cant seem to find this info on RealNet or elsewhere.

Any real estate experts who can help me?

thanks.