saving configuration into seperate files

hello all,
I have a file with 10 configurations. its size is say 20mb . (sayeach configuration would take 2 mb size if they are created asseperate files. Just for an example).

When i try to creat a seperate files using the 10 configurationfile(20Mb) (ie. deleting 9 configurations) the file size of the newfile with only one configuration is 18Mb. what could i do to reducethe file size when i try to create a file from already availableconfiguration file?

Thanks & RegardsSolidworksParts And Features