id: 4 yr ( 11, (10, 0, 1, 0)) (( 6.6, 6.9 ), ( 5.5, 3.7 ))
 +17              |                 +17 
               |                  
               |               2021  
+    +    +    +    +    +    +   
               |                  
               |                  
               |                  
               |                  
+    +    +    +    +    +    +   
               |                  
               |     2017 2018          
               |   2016 2019            
               |  20142013              
+    +    +    + 2015 122020 +    +    +   
               |                  
               |                  
               |                  
               |                  
+----+----+----+----+----+----+---
               |                  
               |                  
               |                  
               |                  
+    +    +    +    +    +    +   
               |                  
               |                  
               |                  
               |                  
+    +    +    +    +    +    +   
               |                  
  2011            |                  
               |                  
 -13              |                 -15