Novak Djokovic, Roger Federer, Rafael Nadal, Pete Sampras, Andre Agassi, Jimmy Connors, Ivan Lendl, John McEnroe and Björn Borg. Those are the big names in Tennis.
Rod Laver was a dominating force in Tennis in the 1960s and some consider him to be the Greatest Tennis player of all time, besides the Big 3. The ATP Ranking as we know it today was only oficially introduced in the mid 70s, however. Do you know which players spent the most weeks at the No. 1 ranking in each decade of the Tennis Open Era?
This video is a bar chart race of the entire ATP Ranking history from 1973 to December 31st of 2021.

This year Novak Djokovic rewrote the history books when surpassed Roger Federer as the man with most weeks spent at the Number 1 spot. He put himself into that position by winning 3 of the 4 Grand Slams in 2021. After his record 9th Australian Open title, he defeated the King of Clay, Rafael Nadal at Roland Garros (the French Open) and then went on to win the Wimbledon title and equal Federer and Nadal's record of 20 Grand Slam tournaments won in their career.
Only Daniil Medvedev, the first man since 2005 other than the Big 3 and Andy Murray to occupy a Top 2 Ranking Position, was able to deny Djokovic a true Calendar Grand Slam in 2021. He defeated Djokovic in the US Open final to win his own first Major tournament.

Novak Djokovic, however, still enjoys a demanding lead in the Rankings and will be in a very good position to add more weeks at the No 1 to his name and to extend his record.
Can anybody, be it Medvedev, Alexander Zverev, Nadal or any other player push the Djoker off the throne?