Table of Contents
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Introduction
Expanding on the experience I am forming analysing the gladiabiots ratings (articles:2017-06:elo-inights here), I noticed that the world of chess, that stimulated the work of Arpad Elo, is missing some analysis on the top ratings. Or maybe those analysis are available but I didn't find them.
Therefore I would like to extend some analysis I did for gladiabots on the FIDE ratings.
Sources and resources
There are many sources online, at least at the moment (yes, internet forgets).
There are different collections of the FIDE ratings, starting before 1970 (the first official fide rating), for example:
- fide ratings list ~1967 to 2001 https://www.olimpbase.org/index.html?https%3A%2F%2Fwww.olimpbase.org%2FElo%2Fsummary.html
- fide ratings 2000 onwards (see ratings on the official fide site)
- 2700chess collection https://www.2700chess.com/top20-for-any-month
- http://www.chessmetrics.com for slightly alternative ratings.
- database of the top20 collected in sqlite until may 2019 or so http://pier4r.pbworks.com/w/browse/#view=ViewFolder¶m=top20fide
- and others I may report other days
For the initial work, as quality builds on time, I will use the ratings of 2700 chess that are easy to use and there is plenty of data.
Remarks
- Actually to have better comparisons players should be active in the periods considered. An inactive player may hold a rating that is actually higher than his current form. Anyway at first I am going to consider the ratings as good representative of the relative strength of a player (ratings are always relative to the playerbase contemporary to the rating!), even if the player doesn't play much. That of course could be wrong in some cases; although it is likely that the rating of a player doesn't change much in a year or so (unless the player is raising quickly).
- I am not going to consider every 2700chess list, rather once in a year (more or less spaced 12 months from the previous one, if possible) presuming that aside from rising players, the others are quite stable.
- By all means this is just one possible perspective on the FIDE ratings list, if you have a better one, go compiling it and then share! I am interested.
- Another important point about ratings is the kfactor (that determines how many points are exchanged in a match in case of a not expected result). It is very likely that the kfactor used in the past by FIDE was different than now, as one can see very "round" scores, always multiple of 5. This may also have helped the formation of larger gaps between scores. To be fair one should compare ratings only when the kfactor used is the same. If the kfactor is very small, for example, accumulating a 20 point gap may be harder compared to a 100 point gap with a larger kfactor. So far, 2018-09-23, I was not able to find the kfactor values pre 2010. Anyway the kfactor difference may matter to compare gaps between different decades, not between players playing at the same time.
- Note that if one player is dominating compared to his contemporaries, his rating is going to explode. This does not mean that he is better than all the future players. An interesting comparison between players of different eras is the CAPS system. That compares each move of renowned chess players against stronger-than-human chess engines to see how many times the move chosen by the player matches the one chosen by the chess engine. Given that the chess engine employed could compute for a specific amount of time. https://www.chess.com/article/view/who-was-the-best-world-chess-champion-in-history . Carlsen, Kasparov and Fisher are very close. Although one can say that Alpha/Beta chess engines play differently from humans and therefore are not that much comparable.
Analyses
Rating distance between ranks.
As I wrote in my other page about the elo insights from the statistics of gladiabots, the Elo's formula is based on rating differences. Rating differences are used to compute the expected result. Therefore the larger the rating gap between players, the larger the gap in average performance between the two players, with the player having the higher score being better.
Let's pick the elo formula component for the expected result
(1)having the player B at 1000 points and the player A at 600, so 400 points of difference, implies that the player B is expected to win 90% of the time. The formula is based on differences. The expected winning percentage remains the same even if B has 1 000 001 000 points and A has 1 000 000 600 points, even though 400 points when one score is 600 seems a lot, while 400 points when one score is 1 000 000 600 seems nothing.
Not only this. Measuring distances between ratings of different ranks (for example: no5 vs no20) gives also an idea how the strength in the field is distributed.
To avoid considering only the very top players, that may play not much, after a while I am considering the ranks immediately under the no1, as there should be always someone playing in the, say, top5, and therefore the ratings are more "live".
Notice also that if a player has a high rating but he doesn't play, there is little to do, he is not going to lose points.
Rating distance no1 vs no2
year | no1 rating | no2 rating | distance | no1 player | no2 player | notes |
---|---|---|---|---|---|---|
1967.06 | 2670 | 2670 | 0 | Spassky | Fischer | |
1968.04 | 2710 | 2690 | 20 | Fischer | Botvinnik | |
1969.01 | 2720 | 2690 | 30 | Fischer | Spassky | |
1970.01 | 2720 | 2670 | 50 | Fischer | Korchnoi | |
1971.01 | 2740 | 2690 | 50 | Fischer | Spassky | |
1972.07 | 2785 | 2660 | 125 | Fischer | Spassky | |
1973.07 | 2780 | 2660 | 120 | Fischer | Karpov | |
1974.05 | 2700 | 2670 | 30 | Karpov | Korchnoi | Fischer first at 2780 but not playing, so skipped this time |
1975.01 | 2705 | 2665 | 40 | Karpov | Korchnoi | Fischer again skipped at 2780 |
1976.01 | 2695 | 2670 | 25 | Karpov | Korchnoi | |
1977.01 | 2690 | 2645 | 45 | Karpov | Korchnoi | |
1978.01 | 2725 | 2665 | 60 | Karpov | Korchnoi | |
1979.01 | 2705 | 2695 | 10 | Karpov | Korchnoi | |
1980.01 | 2725 | 2705 | 20 | Karpov | Tal | |
1981.01 | 2690 | 2650 | 40 | Karpov | Portisch | |
1982.01 | 2720 | 2655 | 55 | Karpov | Timman | |
1983.01 | 2710 | 2690 | 20 | Karpov | Kasparov | |
1984.01 | 2710 | 2700 | 10 | Kasparov | Karpov | |
1985.01 | 2715 | 2705 | 10 | Kasparov | Karpov | |
1986.01 | 2720 | 2700 | 20 | Kasparov | Karpov | |
1987.01 | 2735 | 2710 | 25 | Kasparov | Karpov | |
1988.01 | 2750 | 2715 | 35 | Kasparov | Karpov | |
1989.01 | 2775 | 2750 | 25 | Kasparov | Karpov | |
1990.01 | 2800 | 2730 | 70 | Kasparov | Karpov | |
1991.01 | 2800 | 2725 | 75 | Kasparov | Karpov | |
1992.01 | 2780 | 2725 | 55 | Kasparov | Karpov | |
1993.01 | 2805 | 2725 | 80 | Kasparov | Karpov | |
1994.01 | 2740 | 2715 | 25 | Karpov | Shirov | Kasparov had problems with FIDE |
1995.01 | 2805 | 2765 | 40 | Kasparov | Karpov | |
1996.01 | 2775 | 2775 | 0 | Kramnik | Kasparov | |
1997.01 | 2795 | 2765 | 30 | Kasparov | Anand | |
1998.01 | 2825 | 2790 | 35 | Kasparov | Kramnik | |
1999.01 | 2812 | 2781 | 31 | Kasparov | Anand | first year that the ratings do not seem rounded to a multiple of 5 |
2000.01 | 2851 | 2769 | 82 | Kasparov | Anand | |
2001.01 | 2849 | 2790 | 59 | Kasparov | Anand | |
2002.01 | 2838 | 2809 | 29 | Kasparov | Kramnik | |
2003.01 | 2847 | 2809 | 38 | Kasparov | Kramnik | |
2004.01 | 2831 | 2777 | 54 | Kasparov | Kramnik | |
2005.01 | 2804 | 2786 | 18 | Kasparov | Anand | |
2006.01 | 2812 | 2801 | 11 | Kasparov | Topalov | |
2007.01 | 2783 | 2779 | 4 | Topalov | Anand | |
2008.01 | 2799 | 2799 | 0 | Kramnik | Anand | |
2009.01 | 2796 | 2791 | 5 | Topalov | Anand | |
2010.01 | 2810 | 2805 | 5 | Carlsen | Topalov | |
2011.01 | 2814 | 2810 | 4 | Carlsen | Anand | |
2012.01 | 2835 | 2805 | 30 | Carlsen | Aronian | |
2013.01 | 2861 | 2810 | 51 | Carlsen | Kramnik | |
2014.01 | 2872 | 2812 | 70 | Carlsen | Aronian | |
2015.01 | 2862 | 2820 | 42 | Carlsen | Caruana | |
2016.01 | 2844 | 2801 | 43 | Carlsen | Kramnik | |
2017.01 | 2840 | 2827 | 13 | Carlsen | Caruana | |
2018.01 | 2834 | 2811 | 23 | Carlsen | Caruana | |
2018.09 | 2839 | 2827 | 12 | Carlsen | Caruana |
Top 5 distances no1 vs no2, showing the domination of a player over the rest of his contemporaries.
year | no1 rating | no2 rating | distance | no1 player | no2 player | notes |
---|---|---|---|---|---|---|
1972.07 | 2785 | 2660 | 125 | Fischer | Spassky | |
1973.07 | 2780 | 2660 | 120 | Fischer | Karpov | |
2000.01 | 2851 | 2769 | 82 | Kasparov | Anand | |
1993.01 | 2805 | 2725 | 80 | Kasparov | Karpov | |
1991.01 | 2800 | 2725 | 75 | Kasparov | Karpov |
Rating distance no1 vs no5
year | no1 rating | no5 rating | distance | no1 player | no5 player | notes |
---|---|---|---|---|---|---|
1967.06 | 2670 | 2650 | 20 | Spassky | Tal | |
1968.04 | 2710 | 2650 | 60 | Fischer | Larsen | |
1969.01 | 2720 | 2650 | 70 | Fischer | Petrosian | |
1970.01 | 2720 | 2650 | 70 | Fischer | Larsen | |
1971.01 | 2740 | 2640 | 100 | Fischer | Petrosian | |
1972.07 | 2785 | 2640 | 145 | Fischer | Portisch | |
1973.07 | 2780 | 2650 | 130 | Fischer | Portisch | |
1974.05 | 2700 | 2645 | 55 | Karpov | Portisch | Fischer first at 2780 but not playing, so skipped this time |
1975.01 | 2705 | 2645 | 60 | Karpov | Polugaevsky | Fischer again skipped at 2780 |
1976.01 | 2695 | 2630 | 65 | Karpov | Spassky | |
1977.01 | 2690 | 2625 | 65 | Karpov | Portisch | |
1978.01 | 2725 | 2630 | 95 | Karpov | Spassky | |
1979.01 | 2705 | 2625 | 80 | Karpov | Timman | |
1980.01 | 2725 | 2635 | 90 | Karpov | Polugaevsky | |
1981.01 | 2690 | 2635 | 55 | Karpov | Spassky | |
1982.01 | 2720 | 2630 | 90 | Karpov | Portisch | |
1983.01 | 2710 | 2625 | 85 | Karpov | Huebner | |
1984.01 | 2710 | 2630 | 80 | Kasparov | Andersson | |
1985.01 | 2715 | 2635 | 80 | Kasparov | Portisch | |
1986.01 | 2720 | 2645 | 75 | Kasparov | Yusupov | |
1987.01 | 2735 | 2625 | 110 | Kasparov | Korchnoi | |
1988.01 | 2750 | 2640 | 110 | Kasparov | Korchnoi | |
1989.01 | 2775 | 2640 | 135 | Kasparov | Speelman | |
1990.01 | 2800 | 2645 | 155 | Kasparov | Gurevich Mikhail | |
1991.01 | 2800 | 2650 | 150 | Kasparov | Bareev | |
1992.01 | 2780 | 2670 | 110 | Kasparov | Anand | |
1993.01 | 2805 | 2690 | 115 | Kasparov | Gelfand | |
1994.01 | 2740 | 2710 | 30 | Karpov | Kramnik | Kasparov had problems with FIDE |
1995.01 | 2805 | 2715 | 90 | Kasparov | Kramnik | |
1996.01 | 2775 | 2735 | 40 | Kramnik | Kamsky | |
1997.01 | 2795 | 2740 | 55 | Kasparov | Ivanchuk | |
1998.01 | 2825 | 2740 | 85 | Kasparov | Ivanchuk | |
1999.01 | 2812 | 2723 | 89 | Kasparov | Morozevich | first year that the ratings do not seem rounded to a multiple of 5 |
2000.01 | 2851 | 2748 | 103 | Kasparov | Morozevich | |
2001.01 | 2849 | 2745 | 104 | Kasparov | Leko | |
2002.01 | 2838 | 2742 | 96 | Kasparov | Morozevich | |
2003.01 | 2847 | 2736 | 111 | Kasparov | Leko | |
2004.01 | 2831 | 2736 | 95 | Kasparov | Shirov | |
2005.01 | 2804 | 2749 | 55 | Kasparov | Leko | |
2006.01 | 2812 | 2752 | 60 | Kasparov | Aronian | |
2007.01 | 2783 | 2750 | 33 | Topalov | Ivanchuk | |
2008.01 | 2799 | 2763 | 33 | Kramnik | Svidler | |
2009.01 | 2796 | 2771 | 25 | Topalov | Morozevich | |
2010.01 | 2810 | 2781 | 29 | Carlsen | Aronian | |
2011.01 | 2814 | 2776 | 38 | Carlsen | Karjakin | |
2012.01 | 2835 | 2773 | 62 | Carlsen | Radjabov | |
2013.01 | 2861 | 2781 | 80 | Carlsen | Caruana | |
2014.01 | 2872 | 2785 | 87 | Carlsen | Topalov | |
2015.01 | 2862 | 2797 | 65 | Carlsen | Anand | |
2016.01 | 2844 | 2787 | 57 | Carlsen | Caruana | |
2017.01 | 2840 | 2796 | 44 | Carlsen | Vachier-Lagrave | |
2018.01 | 2834 | 2793 | 41 | Carlsen | Vachier-Lagrave | |
2018.09 | 2839 | 2780 | 59 | Carlsen | Vachier-Lagrave |
Top 5 distances no1 vs no5, showing the domination of a player over the rest of his contemporaries.
year | no1 rating | no2 rating | distance | no1 player | no5 player | notes |
---|---|---|---|---|---|---|
1990.01 | 2800 | 2645 | 155 | Kasparov | Gurevich Mikhail | |
1991.01 | 2800 | 2650 | 150 | Kasparov | Bareev | |
1972.07 | 2785 | 2640 | 145 | Fischer | Portisch | |
1989.01 | 2775 | 2640 | 135 | Kasparov | Speelman | |
1973.07 | 2780 | 2650 | 130 | Fischer | Portisch |
Rating distance no5 vs no20
It is incredible to see that the world no1 (for FIDE) is able to distance himself from the no5 more, in some cases, than the no5 is able to distance himself from the no20. The group of players between no5 and no20 was always quite packed together in terms of ratings (and therefore relative strength).
year | no5 rating | no20 rating | distance | no5 player | no20 player | notes |
---|---|---|---|---|---|---|
1967.06 | 2650 | 2580 | 70 | Tal | Hort | |
1968.04 | 2650 | 2590 | 60 | Larsen | Gligoric | |
1969.01 | 2650 | 2590 | 60 | Petrosian | Taimanov | |
1970.01 | 2650 | 2570 | 80 | Larsen | Najdorf | |
1971.01 | 2640 | 2580 | 60 | Petrosian | Gipslis | |
1972.07 | 2640 | 2575 | 65 | Portisch | Vasiukov | |
1973.07 | 2650 | 2585 | 65 | Portisch | Taimanov | |
1974.05 | 2640 | 2595 | 50 | Portisch | Byrne | |
1975.01 | 2645 | 2580 | 65 | Polugaevsky | Taimanov | |
1976.01 | 2630 | 2575 | 55 | Spassky | Ribli | |
1977.01 | 2625 | 2580 | 45 | Portisch | Byrne | |
1978.01 | 2630 | 2575 | 55 | Spassky | Sosonko | |
1979.01 | 2625 | 2590 | 35 | Timman | Ljubojevic | |
1980.01 | 2635 | 2590 | 45 | Polugaevsky | Gulko | |
1981.01 | 2635 | 2585 | 50 | Spassky | Ribli | |
1982.01 | 2630 | 2590 | 40 | Portisch | Ribli | |
1983.01 | 2625 | 2580 | 45 | Huebner | Torre | |
1984.01 | 2630 | 2580 | 50 | Andersson | Romanishin | |
1985.01 | 2635 | 2570 | 65 | Portisch | Miles | |
1986.01 | 2645 | 2575 | 70 | Yusupov | Velimirovic | |
1987.01 | 2625 | 2585 | 40 | Korchnoi | Nunn | |
1988.01 | 2640 | 2595 | 45 | Korchnoi | Seirawan | |
1989.01 | 2640 | 2610 | 30 | Speelman | Seirawan | |
1990.01 | 2645 | 2610 | 35 | Gurevich | Speelman | |
1991.01 | 2650 | 2620 | 30 | Bareev | Huebner | |
1992.01 | 2670 | 2620 | 50 | Anand | Adams | |
1993.01 | 2690 | 2630 | 60 | Gelfand | Adams | |
1994.01 | 2710 | 2630 | 80 | Kramnik | Tiviakov | |
1995.01 | 2715 | 2645 | 70 | Kramnik | Nikolic | |
1996.01 | 2735 | 2650 | 85 | Kamsky | Hracek | |
1997.01 | 2740 | 2650 | 90 | Ivanchuk | Khalifman | |
1998.01 | 2740 | 2660 | 80 | Ivanchuk | Krasenkow | |
1999.01 | 2723 | 2670 | 53 | Morozevich | Timman | first year that the ratings do not seem rounded to a multiple of 5 |
2000.01 | 2748 | 2672 | 76 | Morozevich | Svidler | |
2001.01 | 2745 | 2679 | 66 | Leko | Karpov | |
2002.01 | 2742 | 2683 | 59 | Morozevich | Dreev | |
2003.01 | 2736 | 2688 | 48 | Leko | Karpov | |
2004.01 | 2736 | 2682 | 54 | Shirov | Dreev | |
2005.01 | 2749 | 2685 | 64 | Leko | Volokitin | |
2006.01 | 2752 | 2698 | 54 | Aronian | Bareev | |
2007.01 | 2750 | 2700 | 50 | Ivanchuk | Akopian | |
2008.01 | 2763 | 2711 | 52 | Svidler | Alekseev | |
2009.01 | 2771 | 2723 | 48 | Morozevich | Svidler | |
2010.01 | 2781 | 2723 | 58 | Aronian | Shirov | |
2011.01 | 2776 | 2726 | 50 | Karjakin | Wojtaszek | |
2012.01 | 2773 | 2732 | 41 | Radjabov | Kamsky | |
2013.01 | 2781 | 2734 | 47 | Caruana | Jakovenko | |
2014.01 | 2785 | 2734 | 51 | Topalov | Wang Hao | |
2015.01 | 2797 | 2734 | 63 | Anand | Radjabov | |
2016.01 | 2787 | 2744 | 43 | Caruana | Adams | |
2017.01 | 2796 | 2742 | 54 | Vachier-Lagrave | Grischuk | |
2018.01 | 2793 | 2745 | 48 | Vachier-Lagrave | Harikrishna | |
2018.09 | 2780 | 2742 | 38 | Vachier-Lagrave | Wei Yi |
Concentration of points
Another phenomena I observed working on the gladiabots dataset is that in general the rich gets richer. The strong players slowly go farming points from other players - also retaining points from players that quit playing - and therefore the points slowly accumulate at the top. This can be seen with the amount of points collected in the first positions (in this case top20).
weight top5 and top 20 total points
In a equal rating table, the top5 would have exactly 25% of the ratings points of the top20. One can see that in some moments the top5 was able to add a 0.61% more than its fair share.
What is interesting to notice is that round about the dissolution of the soviet union and then for almost all the years after, the top20 started to accumulating points. As points are created by new players and then move slowly upwards as stronger players collect them. Likely new countries joined FIDE and/or produced more and more rated player that helped injecting points in the system.
year | top5 points | top20 points | top5 % weight | top5 points diff 1 year | top20 points diff 1 year | notes |
---|---|---|---|---|---|---|
1967.06 | 13300 | 52390 | 25.38 | 0 | 0 | |
1968.04 | 13370 | 52530 | 25.45 | 70 | 140 | |
1969.01 | 13400 | 52480 | 25.53 | 30 | -50 | |
1970.01 | 13370 | 52480 | 25.47 | -30 | 0 | |
1971.01 | 13390 | 52520 | 25.49 | 20 | 40 | |
1972.07 | 13375 | 52490 | 25.48 | -15 | -30 | |
1973.07 | 13405 | 52545 | 25.51 | 30 | 55 | |
1974.05 | 13445 | 52640 | 25.54 | 40 | 95 | |
1975.01 | 13440 | 52585 | 25.55 | -5 | -55 | |
1976.01 | 13265 | 52275 | 25.37 | -175 | -310 | |
1977.01 | 13240 | 52260 | 25.33 | -20 | -15 | |
1978.01 | 13280 | 52275 | 25.4 | 40 | 15 | |
1979.01 | 13305 | 52335 | 25.42 | 25 | 60 | |
1980.01 | 13415 | 52430 | 25.58 | 110 | 95 | |
1981.01 | 13260 | 52355 | 25.32 | -155 | -75 | |
1982.01 | 13290 | 52345 | 25.38 | 30 | -10 | |
1983.01 | 13300 | 52290 | 25.43 | 10 | -55 | |
1984.01 | 13310 | 52425 | 25.38 | 10 | 135 | |
1985.01 | 13345 | 52330 | 25.5 | 35 | -95 | |
1986.01 | 13355 | 52390 | 25.49 | 10 | 60 | |
1987.01 | 13360 | 52365 | 25.51 | 5 | -25 | |
1988.01 | 13425 | 52670 | 25.48 | 65 | 305 | |
1989.01 | 13455 | 52690 | 25.53 | 30 | 20 | |
1990.01 | 13520 | 52845 | 25.58 | 65 | 155 | |
1991.01 | 13570 | 53105 | 25.55 | 50 | 260 | |
1992.01 | 13580 | 53145 | 25.55 | 10 | 40 | |
1993.01 | 13640 | 53415 | 25.53 | 60 | 270 | |
1994.01 | 13590 | 53490 | 25.4 | -50 | 75 | |
1995.01 | 13715 | 53750 | 25.51 | 125 | 260 | |
1996.01 | 13790 | 53885 | 25.59 | 75 | 135 | |
1997.01 | 13800 | 53920 | 25.59 | 10 | 35 | |
1998.01 | 13865 | 54110 | 25.62 | 65 | 190 | |
1999.01 | 13793 | 54212 | 25.44 | -72 | 102 | |
2000.01 | 13877 | 54266 | 25.57 | 84 | 54 | |
2001.01 | 13902 | 54427 | 25.54 | 25 | 161 | |
2002.01 | 13888 | 54447 | 25.5 | -14 | 20 | |
2003.01 | 13888 | 54473 | 25.49 | 0 | 26 | |
2004.01 | 13857 | 54557 | 25.39 | -31 | 84 | |
2005.01 | 13850 | 54474 | 25.42 | -7 | -83 | |
2006.01 | 13922 | 54671 | 25.46 | 72 | 197 | |
2007.01 | 13832 | 54702 | 25.28 | -90 | 31 | |
2008.01 | 13906 | 54916 | 25.32 | 74 | 214 | |
2009.01 | 13913 | 55016 | 25.28 | 7 | 100 | |
2010.01 | 13974 | 55073 | 25.37 | 61 | 57 | |
2011.01 | 13989 | 55165 | 25.35 | 15 | 92 | |
2012.01 | 14013 | 55273 | 25.35 | 24 | 108 | |
2013.01 | 14047 | 55370 | 25.36 | 34 | 97 | |
2014.01 | 14045 | 55363 | 25.36 | -2 | -7 | |
2015.01 | 14089 | 55441 | 25.41 | 44 | 78 | |
2016.01 | 14022 | 55473 | 25.27 | -67 | -32 | |
2017.01 | 14082 | 55548 | 25.35 | 60 | 75 | |
2018.01 | 14039 | 55477 | 25.3 | -43 | -71 | |
2018.09 | 14070 | 55520 | 25.34 | 31 | 43 |
Observations
Dominating players in the past used better their resources
The stats shows that the difference of strength is very small in recent years compared to the years until Kasparov dominated (and before that Karpov and then Fisher). Why? My informed guess is the following.
The players that dominated (and dominate) with large margins (80+ points from the no5) have (and had) enormous and very rare personal qualities needed for the challenge (intellectual skills, passion, commitment, and so on). Very rare otherwise they wouldn't have been alone at the top. Also they had an advantage in understanding of the game better than their peers.
I think in recent years the field leveled as it is way easier to do studies online and/or with the help of strong chess programs that provide insights to everyone and not only elite players in elite chess clubs. Therefore the ones in the past that squeezed more information from analyses of games by periodicals, chess clubs, study groups, books and other resources, to then combined those lessons learned with excellent personal qualities had a clear edge on all the others.
Reading around about players from 1900 to 1970 one can see this pattern. Lasker, Rubinstein, Capablanca, Botvinnik, Fischer and others really committed their life to chess (well Lasker up to a certain point) without resting on their laurels or just playing. They extracted more and more information from whatever possible chess source. This especially was true from Fisher, that went to read chess information in other languages, and he indeed accumulated a remarkable distance from the others when he actively played.
Points accumulation to the top and absolute scores to take with a grain of salt rather than gold values
As explained in the section showing the total points of the top20, the ratings start to sharply increase around the fall of the Soviet Union. So around 1989-1990. From there the increase of points is (almost) unstoppable. My informed guess is the following.
Could be that around that time FIDE allowed more players to get rated. Tournaments, where ranked games were played, become more frequent and so points moved around with more velocity, drifting a bit faster towards the top players that were (and are) able to harvest them. One point more here, one point more there.
Now people obsess about a so perceived "inflation" of scores, but this because absolute scores are taken as gold value. What matters, learned the hard way on the gladiabots stats, are score differences. The Elo's formula is pretty consistent, score differences stay the same in a certain pool of players with not so fast changing skills, even if absolute values change.
What could be affected by absolute scores being higher is the number of games needed for a (new) strong player to reach a top score. But normally that doesn't take much more time as well. Since the process of getting strong new players is continuous - as new strong players appear every year - also the top scores cannot get that fast so high as they get remarkable losses from those raising players. So instead of someone needing, say, 100 games, to be in the top 20, one would need 110 games and so on. 10 games more is not a tragedy. Before the additional amount of games needed to reach the top20 by a strong player becomes unfeasible, long time will pass.
This means that 2700chess, for example, some decades ago could have been called 2650chess or 2600chess. And in some decades it will change to 2750chess. Or could also be that the velocity of points accumulating towards the top is somehow stabilizing (that is, no more ever increasing top scores). One can see this by the points accumulated by the top20 in the last 2-3 years. The top 20 starts to lose points as well after decades of ever increasing total points.