Table 03. Average
Number of EMPLOYEE Hours at Metallic
Operations in the United States,
by Primary Activity, 1978-2007
|
Year
|
Underground
Mines
|
Surface
Mines
|
|
|
Underground
|
Surf at UG
|
Total
|
Strip
|
Dredge
|
Other
|
Total
|
|
1978
|
36,742,707
|
8,038,701
|
44,781,408
|
48,522,531
|
805,528
|
138,549
|
49,466,608
|
|
1979
|
38,831,160
|
9,207,178
|
48,038,338
|
52,662,353
|
708,135
|
136,834
|
53,507,322
|
|
1980
|
38,307,900
|
10,283,340
|
48,591,240
|
49,575,691
|
689,497
|
200,024
|
50,465,212
|
|
1981
|
38,686,156
|
10,740,801
|
49,426,957
|
51,874,766
|
665,049
|
31,442
|
52,571,257
|
|
1982
|
24,357,362
|
7,256,644
|
31,614,006
|
30,279,970
|
696,794
|
12,996
|
36,989,760
|
|
19831
|
16,361,866
|
5,277,736
|
21,639,602
|
23,640,652
|
682,118
|
-
|
24,322,770
|
|
1984
|
16,426,707
|
4,225,864
|
20,652,571
|
22,978,455
|
668,343
|
-
|
23,646,798
|
|
1985
|
14,298,452
|
3,644,977
|
17,943,429
|
19,640,548
|
682,147
|
-
|
20,322,695
|
|
1986
|
13,060,046
|
3,156,922
|
16,216,968
|
19,055,356
|
790,254
|
-
|
19,845,610
|
|
1987
|
13,010,347
|
3,155,772
|
16,166,119
|
21,934,385
|
968,112
|
-
|
22,902,497
|
|
1988
|
14,713,725
|
3,497,822
|
18,211,547
|
27,417,137
|
1,124,143
|
-
|
28,541,290
|
|
1989
|
14,865,632
|
3,870,086
|
18,735,718
|
31,944,491
|
1,002,126
|
-
|
32,946,617
|
|
1990
|
14,923,497
|
4,105,080
|
19,028,577
|
34,982,186
|
937,034
|
-
|
35,919,220
|
|
1991
|
13,183,883
|
3,580,859
|
16,764,742
|
34,990,660
|
843,877
|
-
|
35,834,537
|
|
1992
|
11,452,301
|
3,657,552
|
15,109,853
|
34,140,305
|
856,839
|
-
|
34,997,144
|
|
1993
|
10,223,218
|
3,149,483
|
13,372,701
|
34,466,673
|
845,110
|
152,202
|
35,463,985
|
|
1994
|
10,668,653
|
2,687,313
|
13,355,966
|
33,080,463
|
703,042
|
1,350,270
|
35,133,775
|
|
1995
|
11,744,082
|
2,836,751
|
14,580,833
|
35,003,079
|
721,156
|
1,446,697
|
37,170,932
|
|
1996
|
12,189,920
|
2,809,491
|
14,999,411
|
36,794,604
|
799,379
|
1,227,202
|
38,821,185
|
|
1997
|
12,472,635
|
2,700,358
|
15,172,993
|
34,636,009
|
790,174
|
1,049,565
|
36,475,748
|
|
1998
|
11,523,977
|
2,258,278
|
13,782,255
|
30,597,427
|
670,379
|
578,780
|
31,846,586
|
|
1999
|
9,895,473
|
1,968,286
|
11,863,759
|
27,444,739
|
631,235
|
460,252
|
28,536,226
|
|
2000
|
8,813,437
|
2,034,500
|
10,847,937
|
24,931,485
|
566,542
|
478,181
|
25,976,208
|
|
2001
|
8,902,189
|
1,728,611
|
10,630,800
|
23,295,019
|
469,091
|
220,635
|
| |
