19920122
       19800112      70.6
       19800126      70.9
       19820103      76.1
       19820104      74.7
       19820123      77.1
       19820124      76.3
       19850117      74.2
       19860106      71.9
       19860108      70.2
       19880110      70.4
       19910126      73.7
       19920122     100.0
       19920123      80.4
       19940114      72.3
       19970104      70.3
       19980109      71.7
       20000101      71.0
       20000102      75.6
       20030128      75.5
       20030130      71.7
       20040109      75.4