ISSN 1598-4133
0% 20% 40% 60% 80% 100% 1997 1998 1999 2000 2001 2002 (GM)
0 5 10 15 20 25 30 35 40 45 50 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 00
0 5 10 15 20 25 30 35 40 45 50 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 00 /
0 5 10 15 20 25 30 12 13-23 2 3-4 5-9 10-1415-1920 % m edian=3.7 mean=6.9
3.3 3.8 3.5 4.2 4 3.9 4.2 3.4 3.9 4.2 5.3 5.6 6.5 6.3 6.7 7.1 6.7 6.5 6.9 5.6 6.1 0 1 2 3 4 5 6 7 8 1983 1987 1991 1996 1998 2000 2002 ( ) ( )