Empty CAD file 18MB in size

Dear all,

I got the CAD file 18 MB in size although I do audit, purge, recover, wblock but cannot fix this. The problem was resolved when i created new file in ACAD 2011 and copy all information to.

Could you explain what is the difference? I mean ACAD 2013 may contain something affect to file size.

Here is the file's link http://www.mediafire.com/download/039acqe0n2cd29r/X-BA-PL.dwg

Thanks for your help.

Regards,

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