SIGNIFICANT FEATURES OF MIGRATION 49
decennial census periods and the volume of immigration during the
ten years centering at July 1st of the census year. It will be noted
that immigration was relatively greatest in the decade from July
1, 1846, to June 30, 1855, in which period the average annual im-
migration was about equal to one and one-quarter per cent of the
total population. In no subsequent decade has the average annual
ratio of immigration to population fallen below one-half of one per
cent or much exceeded one per cent.
TABLE 9.—AVERAGE ANNUAL IMMIGRATION COMPARED WITH POPULATION,
BY DECADES
AVERAGE ANNUAL IMMIGRATION
Date or CENsUS PopurLaTiON =
(THOUSANDS) NUMBER IRATIO TO POPULA-
(THOUSANDS): TION (PER CENT)
JUNE1-1830......... cc... 12,866 34 .26
JONE1-1840..............." 17,069 77 45
Jung1-1850...............™ 23,192 296 1.28
JUNE I-1860... ............. 31,443 158 .50
JUNE 1-1870...........7 TF. 38,558 338 | .83
JUNE1-1880.......... t=... 50,156 406 81
JUNE 1-1890... .... . 62,948 439 | TY
Jone 1-1900............... 75,995 540 71
APRIL 15-1910... ......7. .. 91,972 942 02
Jan. 1-1020." 0... tT 59 105,711 389s 37
aThe population data are from the 1920 Census, Vol. II, p. 29; the average annual immigration is
computed from data in the 1924 Annual Report of the Commissioner General of Immigration, p. 122, and from
mimeographed bulletins of the U. S. Bureau of Immigration for the last six months of 1924, and, except in
the last case, is the average over ten years centered at July 1st of the census year.
bAverage for ten years centered at January 1, 1920.
If we turn to a year-by-year comparison, we find, as would be
expected, a greater variation in the ratio of immigration to popu-
lation. In Table 10 is given a comparison between the total number
of alien arrivals in fiscal years ending June 30th, and the estimated
population on January 1st of the corresponding years, and also a
comparison between population and the net alien movement—that
18, arrivals less departures.
It should be noted that the data in Table 9 include only those
aliens officially recorded as immigrants, but that in Table 10 and
Table 11 nonimmigrants and nonemigrants are also included; hence
in the immediately following paragraphs the term “immigration”
refers to all arriving aliens.
This estimate of population was prepared by Dr. W. I. King, of the National Bureau
of Economic Research, and is based upon interpolations between the decennial censuses
with the aid of immigration data and the available statistics of births and deaths.
