19880117
       19840115      75.2
       19840116      74.2
       19840117      70.4
       19840131      72.5
       19860118      70.3
       19880117     100.0
       19880122      70.9
       19900114      70.1
       19930101      71.9
       19930115      71.9
       19930129      72.9
       19950116      71.7
       19960127      70.1
       19990119      71.5
       20000115      72.9
       20060117      72.9
       20060118      74.4
       20060121      78.6
       20060122      74.9
       20090113      72.5