What was the average rank for south africa one when had more than 8 silver medal?
Rank Nation Gold Silver Bronze Total
1964 Summer Paralympics
175110
real text real real real real
2-175110-1
Medal table
Medal table
1 United States 50 41 32 123
2 Great Britain 18 23 20 61
3 Italy 14 15 16 45
4 Australia 12 11 7 30
5 Rhodesia 10 5 2 17
6 South Africa 8 8 3 19
7 Israel 7 3 11 21
8 Argentina 6 15 16 37
9 West Germany 5 2 5 12
10 Netherlands 4 6 4 14
SELECT AVG Rank FROM table WHERE Nation = south africa AND Silver > 8
south africa 8