Asset transfer date in prior period resulting in usual depreciation amounts

 Hi-

I am trying to transfer an asset between expense codes/locations, and date the transfer to a previous period.  This asset has been in service for several months, and I'm only back-dating the transfer by one month.

After I process the transfer & generate depreciation, I've noted that the amount of depreciation expense for the 'new' expense coding is an exceedingly high  (over $1million for a $5K asset).  There is a corresponding credit to the 'old' expense code.  The net of the two is the correct depreciation amt - -but the amts per g/l code are way off.

What could cause this?