Exclusive of Puerto Rico.1216
MINERALS YEARBOOK, 1 941

QUARRY AND CRUSHER EMPLOYEES

 From 1929—the first year for which data are available—to 1940
the number of quarry and crusher employees dropped from 5,123 to 4,394, the
average hours per day declined from 9.6 to 7.6, but the tonnage of material
handled per man per hour increased from 3.20 to
4.14. This increase no doubt reflects increased mechanization and greater
efficiency.

Quarry and crusher employees in the portland—cement industry, material
(quarry rock and overburden) handled at quarries included in study, and average
output of material per man in the United States, 1936—40
Year
Employment—quarry and crusher only




Material handl uarry rock



Pe!rflt
dus~
repre
sented'

Average

her of
men
 Time employed

—
A Man-hours
age- Totalnum- man-ber of shifts verage T t 1days  ~  ~ a



Short tons
Percent
of over-
9rder
n
Average per
man (short
toiis)









c U e
Per
shIft
Per
hour

1406    
1407    
1408      
l409'...~.
19403   
ô,023
4,980
4,442
4,433
4,394
246
242
218
234
244
1,233,219
1,203,867
968,873
1,037,183
1,070,881
7.4
7.6
7.6
7.6
76
9,174,710
9,169,763
7,384,387
7,904,793
8,171,104
(2)
(2)
(2)
31,952,378
33,804,500
(2)
(2)
(2)
3.9
2.6
(2)
(2)
(2)
30.81
3L57
(1)
(2)
(2)
4.04
4.14
98.7
900
91)*3
8&3
82.6
' Calculated for each year by dividing quantity of finished cement produced
at mills Included In study by total production.
 ' Figures not available. 2 of Puerto Rico.

HOURS PER DAY

A remarkable change has taken place in the average number of
hours per day of employment. In 1928, 58 percent of the employees
worked more than 9 hours a day; in 1940, only 2 percent. In 1928,
23 percent of the employees had a working day of 11 to 12 hours; in
1940, no employees worked more than 10 hours a day.

Number of men employed in the portland-cement industry in the United States
and
output per man-hour, 1938—40, classified according to hours of labor
per day
Hours per day
1938


19391


1940'



Men employed
~
Num- Percent her of trital

Produc-
tion per
man-*
our
~
Men employed
~___


Num- Percent her of total

Produc-
tion per
man-
hour
~
Men employed



Num- Percent her of total

Produc
tion per
man
hour
~
Less than 6         
6 and less than 7
7 and less than 8   -
8 and less than 9      
9 and less than 10 - - - - -

~
319
6,375
5,608
12, 124
610
1.3
25.5
22.4
48.4
2.4
2.7
2.2
2.3
2.2
1.6
867
7,958
4,345
12,333
3.4
31.2
17.0
48.4
 
2.50
2.42
2.36
2.36
681
6,282
4,679

14,263
133
2.6
24.1
18.0
54.8
-5
2.44
2.62
2.20
2.37

2.29

25,036
100.0
2.2
25,503
100.0
2.38
26,038
100.0
2.40