-----------B--------C--------------D-----------

16-----4/8/13-----------------0 Mo, 0 Da----

17-----3-30-13--------------------------------

Formula in cell D16

INT(MOD(B16-B17,365)/30)&" Mo, "&ROUND(MOD((MOD(B16-B17,365)),30),0)&" Da"

Cell D16 should say 9 Da

Thank you for your help.