http://tennis28.com/slams/games_winpct_year.html
These stats are for the Slems only, but it will probably give a good indication of which seasons to look to for your proposed milestones

@Gary Duane IV.

This correlates VERY well with what I compiled. Unfortunately I could only go back to 1991, but a simple list of all games won and lost for each year by the best players will complete it. That's all I need.

I used the ATP stats and did it the hard way because I wanted to see the balance between aggression and defense.

It turns out it stays pretty steady all year, and a few things become obvious.

Getting to 60% or very close, all year is the usual thing for players who win multiple slams. This shows up for Fed in all his 3 slam years, for Nadal in 2010, Novak in 2011. It also shows up in years when a player only wins one slam but is in contention for all the slams. So Agassi shows up both on this slam list and on my list in 1995. Only one slam, but he was so close in the others. That's not the only time this has happened, not by a long shot.

So Nadal's 2 slam 2013 is on the list, also Nadal's 2011.

Nadal shows up on this list 7 years.

Federer shows up 7 years.

Connors 7 years.

Borg 6 years.

Lendl 6 years.

McEnroe 4 years.

* Novak 3 years, which should now be 4 or 5, because 2015 is not included, and 2014 might be very close.

Becker 3 years.

Vilas 3 years.

Sampras 2 years.

Rosewall 2 years.

Laver 2 years.

Courier 2 years.

Wilander 2 years.

Edberg 2 years.

By the way, 5/7 of the years Connors is in this elite group he was at three of the slams, and we all know why he was not at the AO more often, and when a couple years he was only in two slams. This suggests to me that he continues to be underrated as ONE of the best of all time. I don't have figures for Novak for 2015, but I am absolutely positive that 2015 belongs on this list, and 2014 will be very close.

The biggest anomaly of the Open Era is Sampras, who only made this list a couple times, both for all year and for slams.