MIGRATION AND BUSINESS CYCLES 
the fluctuations in volume are relatively so large that the trend, 
particularly for anything short of very long periods, is to a large 
extent obscured by the violence of the fluctuations. Moreover, on 
closer analysis, it is found that some major elements in migration 
have been declining while others were increasing in number. In all, 
the magnitude of the major fluctuations in immigration has led us 
in some instances, particularly where short periods are under con- 
sideration, to analyze the data without attempting to eliminate 
CHART 1 
FLUCTUATIONS IN THE NUMBER OF IMMIGRANTS, BY YEARS: 
1820-1924. 
1250000 + 
1000000 '- 
720000 ‘- 
300,000 — 
250000F—— ol] 
“lz 50% [77% [8059 | 90-5 rap. 0-79 28 
sNumerical data in Table 1. 
whatever trend may be present; and for long-period studies, in 
order to bring out clearly the current alternations in prosperity and 
depression, trends have been computed by the flexible method of 
the moving average, which tends to eliminate the effect of the 
larger swings such as the general decline from the early eighties to 
the late nineties as well as the general upward trend of immigration. 
The best data for comparing migration and industrial conditions 
apply to the years subsequent to 1890 and particularly to the 
period from 1907 to 1923. Obviously, however, the direction and 
degree of a significant trend throughout this period is largely a 
matter of conjecture. 
24