"Year","1 year","3 year average","5 year average"
1978,1.634105,,
1979,1.629844,1.600831,
1980,1.754908,1.658015,1.642339
1981,1.782744,1.765416,1.735542
1982,1.952098,1.870118,1.844134
1983,2.118991,2.027674,1.966079
1984,2.316174,2.179679,2.124069
1985,2.322165,2.298328,2.341204
1986,2.492756,2.546759,2.599173
1987,3.117348,2.924704,2.782144
1988,3.57454,3.191243,2.983182
1989,3.350481,3.293861,3.115053
1990,3.459837,3.173655,3.23425
1991,3.133561,3.315426,3.234378
1992,3.804484,3.35524,3.248793
1993,3.587564,3.439809,3.265197
1994,3.371229,3.335850,3.35344
1995,3.473318,3.351307,3.499998
1996,3.704671,3.749044,3.705522
1997,4.498144,4.118528,4.041254
1998,4.706749,4.569979,4.419091
1999,5.155183,4.883291,4.656899
2000,5.48694,4.96314,4.608411
2001,5.050199,4.717801,4.53759
2002,4.351037,4.405409,4.492698
2003,4.46001,4.422951,
2004,4.887836,,