Created with Raphaël 2.1.2
0
X
2
4
6
8
10
12
14
16
16.91
1977
9.68
1980
11.82
1985
10.19
1990
15.2
1995
11.09
2000
8.58
2005 February
7.56
2005 October
10.33
2010
10.04
2015
8.05
2020