19840115
       19840114      74.3
       19840115     100.0
       19840116      83.8
       19840131      78.2
       19860117      71.3
       19860118      71.0
       19870106      72.6
       19880117      75.2
       19880118      74.6
       19880120      72.8
       19930101      78.9
       19930115      78.2
       19950116      70.2
       19960127      74.8
       19960129      70.1
       19960130      74.7
       19960131      74.7
       19980101      76.8
       19980106      72.0
       19990119      73.4
       20010117      75.9
       20010118      71.1
       20060117      76.1
       20060121      82.5