New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1907-03-30
CENSUS GUESSKORK.

Many newspapers are publishing in black
face type the estimates of city populations in
1906 just furnished by the federal Census Blu
reau. without enlightening their readers as to
the methods by which the totals given were
obtained No mysterious authority attaches to
the figures produced. and it would be well for
cities whose pride has been swollen or whose
vanity has been wounded to remember that
the Increases reported are in most cases only
mathematical deductions based on past rates
of growth. The method of calculation adopted
by the Census Bureau Is simple and conven-
lent. and it works we'll in dealing with cities
in the mass The calculator takes the growth
in population of given city between 1890 and
1900 and divides it by ten. Then for each year
since 1900 he adds that increment to the city's
actually enumerated population in 1900. AS the
rate of growth of all our cities is fairly uni
form this a priOri estimate fits in many cases,
and its Overestimates for the slower growing
centres are balanced by its underestimate for
the faster growing ones. Yet it is equally clear
that though the general rate of urban progress
IS fairly uniform the rate for individual cities
varies materially from decade To decade, and
no city can be sure that its growth for the last
six years is accurately reflected in an arlth-
metcal process based on its record from 1870
To 1900
The faults of the process are plainly exhibited
three cities of New York, Chicago and Philn-
delphia The totals for Chicago and Philadel-
mia are machine made. Chicago had In 1900
1.69S575 Inhabitants. It's gain for the decade
between 1890 and 1900 nearly 100000.
Its estimated annual growth since 1900 IS
therefore nearly 10000 and its population In
1896 is put at 2.049,1S5. Philadelphia had in
1900 ], 293, 697 inhabitants gain in the 1890
1900 decade of 247O0O It's rate of growth
s#..-1g q on
nually and its population in 1906 is put at
1441.735. Suppose that the same rule IS APP
piled TO New York This city had IN 1900
3. 437. 2O2 inhabitants It's gain in the 1S9O19OO
decade was $4,000, giving an estimated an
nual Increase since 1900 OF $1,000 In 1903 II
should have had a population of 3,99o.OOO. But
the federal estimate Is 4,113,O43. Why IS thisf
Simply because a state enumeration was taken
in 1895 which showed that this city, instead
of having 5000 coo inhabitants. had actually
4O143O4 1t would hardly have done 10 glvo
New York In 1906 a smaller population than
the state enumeration credited It with in 1903
So the federal Census Bureau took the state
figures and added $4,000 as 81 fair guess at
our growth in the last year.
We do not criticise the bureau for using prima
facie and up-to-date returns whenever they are
available But il is misleading TO the general
public which does not realize how the ngures
are obtained, TO put total Tor one Guy reacIicu
by prfor reckoning alongside total Tor an
other city reached by a count of noses. Why
not colIate and repubish such returns as have
a basis in local census operations and leave
out the arbitrary general average hguresE
Anybody who knows the method can get tho
prospective population Of a city which has had
no en- neration since 1900. Only confusion Gan
result ION mixing estimates derived through
varying and inconsistent processes.