why do i get negative results after making click in "calculate"?

Question

At the final process of using OpenLCA i get negative results, for example " -5.9x10^-13  Kg CFC-11-Eq: Container Glass...". Thanks

Comments

Without more information (on e.g. what you calculate, background database, model, LCIA method, avoided product modeling, waste modeling) it is hard to say why. I hope you understand.