Fields across Autocad releases

[sifuentes]

Hi. I work for a company that is still running Autocad 2005. Additionally, all our Autocad seats are set to save to release 2000, due to compatibility issues with some users within and outside the office. We recently begun a project where I would like to take advantage of the formulas you can use in fields, since we have a project that we need to show areas in sq.ft. and sq. meters. I know formulas are available until Autocad 2006. I think I can get the upgrades to 2006 or 7, so we can get the formula feature, but will the field's functionality remain if I keep saving to 2000 format? or if someone using Autocad 2000 opens the drawing and saves it?

Thanks,