Plot of variable(s)
         SPERN4    *
         SEVENT    +

Values for SPERN4  

 1935.4  17.67     !     +                                                    
 1936.1  18.89     !     +                                                    
 1936.2  16.86     !    *+                                                    
 1936.3  17.03     !     +                                                    
 1936.4  16.84     !    *+                                                    
 1937.1  16.14     !    *+                                                    
 1937.2  13.16     !   * +                                                    
 1937.3  11.28     !  *  +                                                    
 1937.4  9.336     ! *   +                                                    
 1938.1  8.763     !*    +                                                    
 1938.2  15.01     !    *+                                                    
 1938.3  19.74     !     +*                                                   
 1938.4  20.64     !     +*                                                   
 1939.1  15.46     !    *+                                                    
 1939.2  14.29     !   * +                                                    
 1939.3  16.07     !    *+                                                    
 1939.4  13.88     !   * +                                                    
 1940.1  12.37     !  *  +                                                    
 1940.2  9.596     ! *   +                                                    
 1940.3  9.870     ! *   +                                                    
 1940.4  10.08     ! *   +                                                    
 1941.1  9.396     ! *   +                                                    
 1941.2  9.037     ! *   +                                                    
 1941.3  8.571     !*    +                                                    
 1941.4  7.491     !*    +                                                    
 1942.1  7.702     !*    +                                                    
 1942.2  8.469     !*    +                                                    
 1942.3  9.415     ! *   +                                                    
 1942.4  9.485     ! *   +                                                    
 1943.1  10.82     ! *   +                                                    
 1943.2  11.23     !  *  +                                                    
 1943.3  11.19     !  *  +                                                    
 1943.4  12.41     !  *  +                                                    
 1944.1  12.92     !  *  +                                                    
 1944.2  14.11     !   * +                                                    
 1944.3  14.20     !   * +                                                    
 1944.4  14.28     !   * +                                                    
 1945.1  14.21     !   * +                                                    
 1945.2  14.96     !    *+                                                    
 1945.3  16.32     !    *+                                                    
 1945.4  18.08     !     +                                                    
 1946.1  20.09     !     +*                                                   
 1946.2  21.94     !     + *                                                  
 1946.3  16.81     !    *+                                                    
 1946.4  14.43     !   * +                                                    
 1947.1  11.94     !  *  +                                                    
 1947.2  10.56     ! *   +                                                    
 1947.3  9.748     ! *   +                                                    
 1947.4  9.503     ! *   +                                                    
 1948.1  8.819     !*    +                                                    
 1948.2  9.000     ! *   +                                                    
 1948.3  7.483     !*    +                                                    
 1948.4  6.638     *     +                                                    
 1949.1  6.328     *     +                                                    
 1949.2  5.900     *     +                                                    
 1949.3  6.519     *     +                                                    
 1949.4  7.224     !*    +                                                    
 1950.1  7.295     !*    +                                                    
 1950.2  6.965     !*    +                                                    
 1950.3  7.151     !*    +                                                    
 1950.4  7.187     !*    +                                                    
 1951.1  7.562     !*    +                                                    
 1951.2  7.706     !*    +                                                    
 1951.3  9.267     ! *   +                                                    
 1951.4  9.742     ! *   +                                                    
 1952.1  10.15     ! *   +                                                    
 1952.2  10.67     ! *   +                                                    
 1952.3  10.40     ! *   +                                                    
 1952.4  11.07     !  *  +                                                    
 1953.1  10.41     ! *   +                                                    
 1953.2  9.618     ! *   +                                                    
 1953.3  9.157     ! *   +                                                    
 1953.4  9.884     ! *   +                                                    
 1954.1  10.56     ! *   +                                                    
 1954.2  11.15     !  *  +                                                    
 1954.3  12.29     !  *  +                                                    
 1954.4  12.99     !   * +                                                    
 1955.1  12.36     !  *  +                                                    
 1955.2  12.74     !  *  +                                                    
 1955.3  12.69     !  *  +                                                    
 1955.4  12.56     !  *  +                                                    
 1956.1  12.60     !  *  +                                                    
 1956.2  13.05     !   * +                                                    
 1956.3  13.40     !   * +                                                    
 1956.4  13.69     !   * +                                                    
 1957.1  12.97     !   * +                                                    
 1957.2  13.85     !   * +                                                    
 1957.3  12.22     !  *  +                                                    
 1957.4  11.87     !  *  +                                                    
 1958.1  13.41     !   * +                                                    
 1958.2  15.44     !    *+                                                    
 1958.3  17.38     !     +                                                    
 1958.4  19.10     !     +*                                                   
 1959.1  17.83     !     +                                                    
 1959.2  17.20     !     +                                                    
 1959.3  16.58     !    *+                                                    
 1959.4  17.67     !     +                                                    
 1960.1  16.32     !    *+                                                    
 1960.2  17.46     !     +                                                    
 1960.3  16.37     !    *+                                                    
 1960.4  17.77     !     +                                                    
 1961.1  21.06     !     + *                                                  
 1961.2  21.33     !     + *                                                  
 1961.3  21.88     !     + *                                                  
 1961.4  22.43     !     + *                                                  
 1962.1  20.64     !     +*                                                   
 1962.2  15.78     !    *+                                                    
 1962.3  15.94     !    *+                                                    
 1962.4  17.19     !     +                                                    
 1963.1  17.94     !     +                                                    
 1963.2  18.07     !     +                                                    
 1963.3  18.11     !     +                                                    
 1963.4  18.66     !     +                                                    
 1964.1  18.89     !     +                                                    
 1964.2  18.87     !     +                                                    
 1964.3  18.83     !     +                                                    
 1964.4  18.63     !     +                                                    
 1965.1  18.41     !     +                                                    
 1965.2  17.38     !     +                                                    
 1965.3  18.06     !     +                                                    
 1965.4  17.81     !     +                                                    
 1966.1  16.71     !    *+                                                    
 1966.2  15.52     !    *+                                                    
 1966.3  13.89     !   * +                                                    
 1966.4  14.47     !   * +                                                    
 1967.1  16.55     !    *+                                                    
 1967.2  17.01     !     +                                                    
 1967.3  18.25     !     +                                                    
 1967.4  18.10     !     +                                                    
 1968.1  16.58     !    *+                                                    
 1968.2  17.88     !     +                                                    
 1968.3  18.14     !     +                                                    
 1968.4  18.03     !     +                                                    
 1969.1  17.44     !     +                                                    
 1969.2  16.73     !    *+                                                    
 1969.3  15.81     !    *+                                                    
 1969.4  15.93     !    *+                                                    
 1970.1  15.92     !    *+                                                    
 1970.2  13.17     !   * +                                                    
 1970.3  15.71     !    *+                                                    
 1970.4  17.96     !     +                                                    
 1971.1  19.22     !     +*                                                   
 1971.2  18.74     !     +                                                    
 1971.3  18.11     !     +                                                    
 1971.4  17.91     !     +                                                    
 1972.1  18.45     !     +                                                    
 1972.2  17.95     !     +                                                    
 1972.3  18.00     !     +                                                    
 1972.4  18.39     !     +                                                    
 1973.1  16.40     !    *+                                                    
 1973.2  14.14     !   * +                                                    
 1973.3  14.10     !   * +                                                    
 1973.4  11.95     !  *  +                                                    
 1974.1  11.24     !  *  +                                                    
 1974.2  9.840     ! *   +                                                    
 1974.3  6.975     !*    +                                                    
 1974.4  7.712     !*    +                                                    
 1975.1  9.865     ! *   +                                                    
 1975.2  11.96     !  *  +                                                    
 1975.3  10.81     ! *   +                                                    
 1975.4  11.33     !  *  +                                                    
 1976.1  11.87     !  *  +                                                    
 1976.2  11.27     !  *  +                                                    
 1976.3  11.02     !  *  +                                                    
 1976.4  10.84     ! *   +                                                    
 1977.1  9.764     ! *   +                                                    
 1977.2  9.643     ! *   +                                                    
 1977.3  9.013     ! *   +                                                    
 1977.4  8.733     !*    +                                                    
 1978.1  8.169     !*    +                                                    
 1978.2  8.507     !*    +                                                    
 1978.3  8.863     !*    +                                                    
 1978.4  7.795     !*    +                                                    
 1979.1  7.638     !*    +                                                    
 1979.2  7.361     !*    +                                                    
 1979.3  7.472     !*    +                                                    
 1979.4  7.264     !*    +                                                    
 1980.1  6.677     *     +                                                    
 1980.2  7.647     !*    +                                                    
 1980.3  8.570     !*    +                                                    
 1980.4  9.161     ! *   +                                                    
 1981.1  9.328     ! *   +                                                    
 1981.2  8.742     !*    +                                                    
 1981.3  7.608     !*    +                                                    
 1981.4  7.979     !*    +                                                    
 1982.1  7.560     !*    +                                                    
 1982.2  7.735     !*    +                                                    
 1982.3  8.881     !*    +                                                    
 1982.4  11.13     !  *  +                                                    
 1983.1  12.32     !  *  +                                                    
 1983.2  13.35     !   * +                                                    
 1983.3  12.49     !  *  +                                                    
 1983.4  11.76     !  *  +                                                    
 1984.1  10.43     ! *   +                                                    
 1984.2  9.456     ! *   +                                                    
 1984.3  10.03     ! *   +                                                    
 1984.4  10.05     ! *   +                                                    
 1985.1  11.02     !  *  +                                                    
 1985.2  12.29     !  *  +                                                    
 1985.3  11.96     !  *  +                                                    
 1985.4  14.46     !   * +                                                    
 1986.1  16.45     !    *+                                                    
 1986.2  17.05     !     +                                                    
 1986.3  15.58     !    *+                                                    
 1986.4  16.72     !    *+                                                    
 1987.1  19.32     !     +*                                                   
 1987.2  21.08     !     + *                                                  
 1987.3  20.29     !     +*                                                   
 1987.4  14.12     !   * +                                                    
 1988.1  13.93     !   * +                                                    
 1988.2  12.55     !  *  +                                                    
 1988.3  12.22     !  *  +                                                    
 1988.4  11.69     !  *  +                                                    
 1989.1  11.81     !  *  +                                                    
 1989.2  12.60     !  *  +                                                    
 1989.3  14.73     !   * +                                                    
 1989.4  15.43     !    *+                                                    
 1990.1  15.67     !    *+                                                    
 1990.2  16.82     !    *+                                                    
 1990.3  14.06     !   * +                                                    
 1990.4  15.47     !    *+                                                    
 1991.1  17.98     !     +                                                    
 1991.2  19.18     !     +*                                                   
 1991.3  21.84     !     + *                                                  
 1991.4  26.22     !     +   *                                                
 1992.1  24.92     !     +  *                                                 
 1992.2  23.94     !     +  *                                                 
 1992.3  23.16     !     +  *                                                 
 1992.4  22.82     !     + *                                                  
 1993.1  22.77     !     + *                                                  
 1993.2  23.31     !     +  *                                                 
 1993.3  22.49     !     + *                                                  
 1993.4  21.32     !     + *                                                  
 1994.1  19.64     !     +*                                                   
 1994.2  17.64     !     +                                                    
 1994.3  16.94     !    *+                                                    
 1994.4  15.01     !    *+                                                    
 1995.1  15.38     !    *+                                                    
 1995.2  15.82     !    *+                                                    
 1995.3  16.61     !    *+                                                    
 1995.4  18.14     !     +                                                    
 1996.1  18.96     !     +*                                                   
 1996.2  19.21     !     +*                                                   
 1996.3  19.09     !     +*                                                   
 1996.4  19.13     !     +*                                                   
 1997.1  18.82     !     +                                                    
 1997.2  21.83     !     + *                                                  
 1997.3  23.31     !     +  *                                                 
 1997.4  24.43     !     +  *                                                 
 1998.1  27.86     !     +    *                                               
 1998.2  29.10     !     +     *                                              
 1998.3  26.70     !     +   *                                                
 1998.4  32.60     !     +      *                                             
 1999.1  33.52     !     +       *                                            
 1999.2  33.46     !     +       *                                            
 1999.3  29.18     !     +     *                                              
 1999.4  30.50     !     +     *                                              
 2000.1  29.41     !     +     *                                              
 2000.2  28.02     !     +    *                                               
 2000.3  26.75     !     +   *                                                
 2000.4  26.41     !     +   *                                                
 2001.1  25.54     !     +   *                                                
 2001.2  33.28     !     +       *                                            
 2001.3  36.77     !     +        *                                           
 2001.4  46.50     !     +             *                                      
 2002.1  46.45     !     +             *                                      
 2002.2  37.02     !     +        *                                           
 2002.3  27.14     !     +    *                                               
 2002.4  31.89     !     +      *                                             
 2003.1  27.97     !     +    *                                               
 2003.2  28.21     !     +    *                                               
 2003.3  25.82     !     +   *                                                
 2003.4  22.81     !     + *                                                  
 2004.1  21.66     !     + *                                                  
 2004.2  20.32     !     +*                                                   
 2004.3  19.29     !     +*                                                   
 2004.4  20.70     !     +*                                                   
 2005.1  19.57     !     +*                                                   
 2005.2  18.80     !     +                                                    
 2005.3  18.46     !     +                                                    
 2005.4  17.85     !     +                                                    
 2006.1  17.82     !     +                                                    
 2006.2  17.05     !     +                                                    
 2006.3  17.00     !     +                                                    
 2006.4  17.40     !     +                                                    
 2007.1  17.09     !     +                                                    
 2007.2  17.70     !     +                                                    
 2007.3  19.42     !     +*                                                   
 2007.4  22.19     !     + *                                                  
 2008.1  21.90     !     + *                                                  
 2008.2  24.92     !     +  *                                                 
 2008.3  25.38     !     +   *                                                
 2008.4  60.70     !     +                    *                               
 2009.1  116.3     !     +                                                *   
 2009.2  122.4     !     +                                                   *
 2009.3  84.30     !     +                                *                   
 2009.4  21.88     !     + *                                                  
 2010.1  19.19     !     +*                                                   
 2010.2  15.36     !    *+                                                    
 2010.3  15.88     !    *+                                                    
 2010.4  16.26     !    *+                                                    
 2011.1  16.31     !    *+                                                    
 2011.2  15.75     !    *+                                                    
 2011.3  13.01     !   * +                                                    
 2011.4  14.46     !   * +                                                    
 2012.1  15.91     !    *+                                                    
 2012.2  15.49     !    *+                                                    
 2012.3  16.66     !    *+                                                    
 2012.4  16.49     !    *+                                                    
 2013.1  17.89     !     +                                                    
 2013.2  17.66     !     +                                                    
 2013.3  17.82     !     +                                                    
 2013.4  18.45     !     +                                                    
 2014.1  18.57     !     +                                                    
 2014.2  19.01     !     +*                                                   
 2014.3  18.61     !     +                                                    
 2014.4  20.12     !     +*                                                   
 2015.1  20.84     !     +*                                                   
 2015.2  21.74     !     + *                                                  
 2015.3  21.18     !     + *                                                  
 2015.4  23.62     !     +  *                                                 
 2016.1  23.83     !     +  *                                                 
 2016.2  24.15     !     +  *                                                 
 2016.3  24.34     !     +  *                                                 
 2016.4  23.68     !     +  *                                                 
 2017.1  23.56     !     +  *                                                 
 2017.2  23.30     !     +  *                                                 
 2017.3  23.53     !     +  *                                                 
 2017.4  24.33     !     +  *                                                 
 2018.1  22.88     !     + *                                                  
 2018.2  22.19     !     + *                                                  
 2018.3  22.35     !     + *                                                  
 2018.4  18.94     !     +                                                    
 2019.1  21.09     !     + *                                                  
 2019.2  21.75     !     + *                                                  
 2019.3  22.40     !     + *                                                  
 2019.4  23.16     !     +  *                                                 
 2020.1  22.22     !     + *                                                  
 2020.2  31.24     !     +      *                                             
 2020.3  34.24     !     +       *                                            
 2020.4  39.90     !     +          *                                         
 2021.1  30.99     !     +     *                                              
 2021.2  27.07     !     +    *                                               
 2021.3  24.56     !     +  *                                                 
 2021.4  24.09     !     +  *                                                 
 2022.1  22.89     !     + *                                                  
 2022.2  19.69     !     +*                                                   
 2022.3  19.17     !     +*                                                   
 2022.4  22.23     !     + *                                                  
 2023.1  23.46     !     +  *                                                 
 2023.2  24.59     !     +  *                                                 
 2023.3  23.27     !     +  *