■\ 



98 



FIGURE 2 



I I T » f ■ ¥ I I f W » ■ ?- ■» | 



« ™ y ■ ^ 



60 6S 70 



February Mm* VWbMlty 



7S 



80 



8S 



90 



7S 80 



Year (I9ra) 



