1968 06 31.97  25.24  28.60 
1968 07 32.07  23.25  27.66 
1968 08 31.93  25.70  28.81 
1968 10 32.31  25.30  28.80 
1968 11 31.75  24.82  28.28 
1969 01 30.65  24.16  27.40 
1969 02 32.16  25.43  28.80 
1969 03 30.59  23.41  27.00 
1969 04 31.77  24.98  28.37 
1969 05 32.25  24.29  28.27 
1969 06 32.21  25.38  28.79 
1969 07 33.89  24.22  29.05 
1969 09 31.40  24.36  27.88 
1969 10 31.96  25.19  28.57 
1969 11 31.40  24.73  28.06 
1969 12 30.85  24.91  27.88 
1970 01 30.45  24.41  27.43 
1970 02 31.11  24.14  27.62 
1970 03 31.38  24.79  28.08 
1970 04 31.21  24.58  27.89 
1970 05 31.73  25.00  28.36 
1970 06 31.15  24.74  27.94 
1970 09 32.04  23.41  27.72 
1970 10 32.43  23.98  28.20 
1970 11 32.03  23.80  27.91 
1970 12 32.62  24.15  28.38 
1971 01 32.02  23.74  27.88 
1971 02 32.52  24.15  28.33 
1971 03 32.00  24.01  28.00 
1971 04 30.73  23.64  27.18 
1971 05 31.60  24.29  27.94 
1971 06 31.48  24.04  27.76 
1971 07 31.41  24.19  27.80 
1971 08 31.55  24.34  27.94 
1971 09 31.90  24.46  28.18 
1971 10 32.03  24.64  28.33 
1971 11 30.68  24.33  27.50 
1971 12 31.50  24.79  28.14 
1972 01 30.09  23.87  26.98 
1972 02 31.04  24.25  27.64 
1972 03 30.86  24.45  27.65 
1972 04 30.10  23.59  26.84 
1972 05 29.68  22.21  25.94 
1972 06 30.06  24.61  27.33 
1972 07 29.09  24.24  26.66 
1972 11 30.34  25.00  27.67 
1972 12 30.10  25.04  27.57 
1973 01 31.04  24.73  27.88 
1973 02 31.72 -99.99 -99.99 
1973 03 31.62  24.85  28.23 
1973 08 31.72  25.02  28.37 
1973 09 30.97  24.52  27.74 
1973 10 30.75  23.83  27.29 
1973 11 30.68  24.65  27.66 
1974 01 30.75  24.26  27.50 
1974 02 30.94  24.46  27.70 
1974 03 29.97  23.72  26.84 
1974 04 30.45  23.69  27.07 
1974 12 30.65  23.44  27.04 
1975 01 30.39  23.85  27.12 
1975 07 31.06  24.28  27.67 
1975 08 31.01  23.78  27.39 
1975 09 31.68  24.64  28.16 
1975 11 31.15  24.27  27.71 
1976 01 31.98  23.69  27.83 
1976 02 30.97  23.87  27.42 
1976 03 30.63  23.60  27.11 
1976 07 29.55  23.85  26.70 
1976 10 31.14  24.05  27.59 
1976 11 31.23  24.23  27.73 
1977 01 31.15  24.31  27.73 
1977 02 30.60  23.60  27.10 
1977 03 31.15  23.76  27.45 
1977 04 30.84  23.47  27.15 
1977 05 31.30  23.63  27.46 
1977 06 30.97  23.38  27.17 
1977 07 31.44  23.47  27.45 
1977 08 30.55  22.76  26.65 
1978 01 30.47  25.08  27.77 
1978 07 31.25  25.38  28.31 
1978 10 31.99  23.66  27.82 
1987 01 30.41  23.53  26.97 
1987 02 29.95  23.65  26.80 
