10 -YEAR RECORDS 

 1921 - 1930 



H 1 1 1 h 



-0.5 

 1.0' 

 0.5 



0.5 -. 



1931 - 1940 



H 1 1 h 



1941 - 1950 



H— ^••••W. 



1951 - 1960 



H h 



-0.5 



50 100 



LAG (DAYS) 



20 -YEAR RECORDS 

 1921 - 1940 



H 1 1 1 h 



1941 - 1960 



H 1 h 



40 -YEAR RECORD 

 1921 - 1960 



H h 



50 100 



LAG (DAYS) 



Figure 4. (Continued) 



15 



