CONCENTRATION OF USE 107

From all this it appears that library circulation serves a
highly specialized clientele.”

TABLE 39

BorrowING OF FicrioN BY CoNCENTRATION OF USE, MONTCLAIR,
N.J., Free Pusric LiBrRARY, 1945 AND 1047

Number of Books Percentage of Fiction

Borrowed of Total Adult Loans

during Year ‘ 1945 1947

Over 70 (“heavy” users) 74 75

30-69 66 59

1029 . 52 51

Under 10 (“light” users) 44 38
ACTUAL USE OF LIBRARY-CIRCULATED BOOKS Not only dO

registration and circulation data need to be interpreted in
the light of intensity of use, but also the validity of cir-
culation statistics as an index to actual reading should be
analyzed. Circulation and actual reading may differ in two im-
portant ways: in the first place, not all books circulated from
the public library may be read; in the second place, someone
other than or in addition to the borrower may read them.
Thus, in one sense, library circulation figures may overesti-
mate actual reading, and in another, they may underestimate
the library’s contribution to the community’s reading.
Every practicing librarian knows that not all borrowers of
books use their own library cards or, indeed, have cards to
use, and general surveys have confirmed this fact. Only 72
percent of actual users of the library during the year had
their own library cards;® about 21 percent used someone

"Unfortunately, there are no similar data describing concentration among
the users of the reference and information services of the public library, or
concentration among the users of the library as a whole (including circula-
tion, reference, and other services). The latter type of data would reveal
what is not now known, namely, whether the same or different people use
the circulation and reference services of the public library.

*SRC, 1948.