SUICIDE IN AUSTRALIA : A STATISTICAL ANALYSIS OF THE FACTS. 229 



linear progression does not very satisfactorily accord with 

 the facts. Such a progression would be represented by 

 the formula 



(1) S = 1118 + 6*5 (T - 1884), 



and is shewn in the figure by the dotted straight line. The 

 general trend is however much better exhibited by the 

 curve shewn by the heavy firm line. This has a 46-year 

 period and gives for the average annual rate of suicide 



(2) S = 1118 + 167 sin 2^ (T ~* 886) 



ja fluctuation reaching a maximum of only 15°/°. 



In these formulae S is the number of persons annually 

 committing suicide for an Australian population of 

 10,000,000, and T is the year in question. The results 

 have been calculated graphically only, the material hardly 

 warranting the application of more rigorous methods. 



Owing to the fact that the masculinity (number of males 

 to one female) of the Australian population has changed 

 from about 1*40 for 1860 to about I'll for 1910, the ratios 

 in the table for the earlier years are somewhat higher than 

 they would be with a population constituted as it now is, 

 since with a masculinity of about 1*10, 83°/° of suicides are 

 males (see next section). The application of the correc- 

 tion would however yield nothing material so far as the 

 present data are concerned, and has been neglected. 



This average rate of suicide for the period 1858 to 1910 

 of 111*8 per million does not exceed very greatly the rate 

 for England and Wales. For comparison the results are 

 given for various countries for successive quinquennia from 

 1871 onwards, and are as follows : — 



