THE PRE-WAR QUARTER CENTURY i 
preparatory to the construction of an index of business conditions, 
puts immigration with the Business Group, which includes clearings, 
pig iron production, pig iron prices, commodity prices, imports, 
building, and railroad earnings; Babson groups immigration with 
new building, commercial failures, and clearings: and Persons, with 
pig iron production, prices, ete. 
Departing Steerage Passengers. 
In examining the depression periods of 1894 and 1904, we have 
noted incidentally that the volume of departing steerage passengers 
furnishes a rough index of emigration. Also, beginning in July, 
1907, official statistics of emigration are available; hence, before 
we turn to a comparison of employment and migratory movements 
in the depression of 1908, it will be of advantage to note the chief 
characteristics of the emigration movement and its relation to 
immigration. 
As previously noted, official statistics of emigration are lacking 
prior to July, 1907, but for most of the years subsequent to the 
Civil War there are statistics of the number of departing passengers, 
made available to the Government by the courtesy of the steamship 
companies. These data are classified as “cabin” and “other than 
cabin” or steerage passengers, and also by sex. The male steerage 
passengers probably afford the best index of the departures of alien 
workers from this country. The ratio of the number of departing 
male steerage passengers to the number of incoming male im- 
migrants affords an approximate measure of the response of the net 
migration of workers to employment opportunity in this country. 
This ratio is not to be taken as representing the exact numerical 
relation of incoming immigrants to departing emigrants, for the 
numerator of the ratio, male immigrants, does not include those 
coming for a temporary sojourn (the non-immigrant group); while 
the denominator, “other than cabin” passengers, is not, in all 
probability, a complete count of emigrant aliens, though it doubtless 
includes some nonemigrant aliens and some citizens of the United 
States. For example, in the years (fiscal) 1908 and 1909 the num- 
ber of departing male steerage passengers was 578,097 and the 
number of officially recorded male emigrant aliens was 501,892. 
However, it is probable that such differences are relatively constant, 
and hence when the ratio of departing steerage passengers to in- 
coming immigrants is low it is an indication that emigration is light 
as compared to immigration. If the ratio is high when industrial 
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