I looked at some numbers before and after Nadal took #1 from Federer after 2008 Wimbledon. It is widely accepted that Federer was out of his peak by that point when he had just turned 27. This is actually the average age of Nadal and Djokovic right now. Doesn't look like they're slowing down due to age anytime soon, yet one could argue their style of play is much more punishing on their bodies than Federer's.
Either way, let's look at overall win pct. and GS win pct. before and after 2008 Wimbledon for Federer, Nadal, and Djokovic.
Overall Win Pct.
Before and including 2008 Wimbledon:
Nadal - 309-73 (80.9%)
Federer - 594-143 (80.6%)
Djokovic - 159-60 (73%)
After:
Nadal - 349-56 (86%)
Djokovic - 384-72 (84%)
Federer - 329-72 (82%)
GS Win Pct.
Before and including 2008 Wimbledon:
Federer - 155-25 (86%)
Nadal - 75-13 (85%)
Djokovic - 46-14 (77%)
After:
Nadal - 96-10 (91%)
Djokovic - 112-16 (88%)
Federer - 105-16 (87%)
What stands out to me is that Federer's overall win pct. and GS win pct. is actually better after 2008 Wimbledon than before (this includes his down year in 2013). There is clear improvement for Nadal after and Djokovic was obviously at a much higher level after.
The place where you see the dropoff for Federer is in the H2H against the players that he has met the most times (the top 4 for him are Nadal, Djokovic, Hewitt, and Roddick). Looking at those 4 his H2H before and including 2008 Wimbledon is 41-23 (64%) and after it is 24-25 (49%).
It looks like Federer's results against the majority of the field have actually improved after the age of 27. Where he's done worse is against the players that he faces the most, mainly Nadal and Djokovic, who have clearly improved after that point. Does this mean his overall level dropped, or a few players improved and surpassed him?
Either way, let's look at overall win pct. and GS win pct. before and after 2008 Wimbledon for Federer, Nadal, and Djokovic.
Overall Win Pct.
Before and including 2008 Wimbledon:
Nadal - 309-73 (80.9%)
Federer - 594-143 (80.6%)
Djokovic - 159-60 (73%)
After:
Nadal - 349-56 (86%)
Djokovic - 384-72 (84%)
Federer - 329-72 (82%)
GS Win Pct.
Before and including 2008 Wimbledon:
Federer - 155-25 (86%)
Nadal - 75-13 (85%)
Djokovic - 46-14 (77%)
After:
Nadal - 96-10 (91%)
Djokovic - 112-16 (88%)
Federer - 105-16 (87%)
What stands out to me is that Federer's overall win pct. and GS win pct. is actually better after 2008 Wimbledon than before (this includes his down year in 2013). There is clear improvement for Nadal after and Djokovic was obviously at a much higher level after.
The place where you see the dropoff for Federer is in the H2H against the players that he has met the most times (the top 4 for him are Nadal, Djokovic, Hewitt, and Roddick). Looking at those 4 his H2H before and including 2008 Wimbledon is 41-23 (64%) and after it is 24-25 (49%).
It looks like Federer's results against the majority of the field have actually improved after the age of 27. Where he's done worse is against the players that he faces the most, mainly Nadal and Djokovic, who have clearly improved after that point. Does this mean his overall level dropped, or a few players improved and surpassed him?