Work allocation

i wanted to allocate jobs to my staffs based on the open jobs that is generated from the system. Say for instance , i have 100 open jobs today and i want to allocate 20 jobs each to 5 staffs each. Need an excel file that could allocate these randomly to these staffs. Next day again the system will populate another set of open jobs which may include the jobs that were already given to these 5 staffs the previous day. I want to have an excel file that would ignore such jobs that have already been allocated and allot jobs that are not allocated at all. This will be a continuous process