1988  -1.0  -1.0  -1.0  -1.0
 1989  -1.0  -1.0  -1.0  -1.0
 1990  -1.0  -1.0  -1.0  -1.0
 1991   1.2   5.9   0.0   0.0
 1992  -1.0  -1.0  -1.0  -1.0
 1993   1.8   4.6   1.2   1.1
 1994  -1.0  -1.0  -1.0  -1.0