From ATPtour.com….
Novak Djokovic has today set the record for most weeks at No. 1 in the 48-year history of the FedEx ATP Rankings.
Djokovic, who captured his ninth Australian Open trophy and 18th Grand Slam title last month, also holds a record 36 ATP Masters 1000 trophies and first attained the No. 1 ranking on 4 July 2011. He has since held the top spot in the rankings across five different stints for a record 311 weeks, one week longer than Roger Federer, who broke Pete Sampras’ record of 286 weeks at No. 1 on 16 July 2012.