1. A method implemented by a processor, the method comprising: extracting collaboration data from a plurality of computer systems of a plurality of collaborators and storing the collaboration data as a dataset, the collaboration data reflecting sent emails in mailboxes and a plurality of meetings in calendars, the sent emails and plurality of meetings being provided by the plurality of computer systems; defining a plurality of attributes for the plurality of collaborators; defining a group of collaborators by filtering based at least on the plurality of attributes; and assigning collaboration time for individual members of the group using the collaboration data of the dataset, the assigning comprising a meeting de-duplication process involving: determining whether two or more meetings of the plurality of meetings comprise overlapping times for one or more attendees; and in response to determining that the two or more meetings comprise overlapping times for the one or more attendees, adjusting time durations for the two or more meetings, such that the adjusted time durations do not exceed an actual time duration for the two or more meetings.