Soviet Players on the FIDE Rating Lists

Having managed to collect some data for FIDE ratings since their inception (see FIDE Historical Ratings 1971-79 for details), I decided to look at the evolution of Soviet players on the lists. The following table shows the count of Soviet players per year.

1971:   74 URS
1972: 108
1973: 211
1974: 213
1975: 282 USR
1976: 266
1977: 265
1978: 273
1979: 317
1980: 388
1981: 417
1982: 446
1983: 434
1984: 366
1985: 395
1986: 353
1987: 360
1988: 448
1989: 537
1990: 695
1991:

The switch of federation codes from URS to USR in 1975 is a reminder that the data comes from multiple sources and is not 100% reliable.

Note how the count of Soviet players drops to zero in 1991. I'll look at this in more detail in another post on the subject. It might also be useful to investigate why the counts drop in certain years, e.g. 1982-83-84 and 1985-86.