Any ideas how to discover/approximate staff numbers per location?

[SteveM77]

Hi, I'm launching a business that needs to target office locations with over 500 employees only. I have tried to find publically available data showing the number of staff members a company may have in a specific location (many large firms have nuerous locations so I do need the staff count data at a location level).

Does anyone know of a resource I have missed that would tell me that or can anyone think of a way to approximate staff numbers laterally?

Any help would be greatly appreciated.

Thanks

 

[Newchodge]

Count the windows and multiply by x?

 

[Creamcrackered]

I don't think there is an easy way of doing it. But if you "Top 100 companies in {insert city/county name}" you'll can track down publications that list the top companies in the area giving the T/O and number of employees. Typically they are put together by the local paper or enterprise agency. I'd post a link to an example but as a newbie I'm allowed to.