TABLE 15. — Thinning of the and I- groups with partia l 

 protection for the II and III groups. 



Without thinning 



liith thinning of groups 

 and I 



Year Group Strenrth Percentage 

 ^ of decline 



Strength 



Percentage 

 of decline 







I 



II 



III 



IV 



V 



VI 



VII 



1,000 

 600 



360 



270 

 200 



100 

 50 

 25 



25% 

 25% 

 50% 

 50% 

 50% 



74 



