Table
01. Number of Nonmetallic 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
|
119
|
7
|
126
|
1,110
|
4
|
21
|
1,135
|
|
1979
|
108
|
4
|
112
|
1,060
|
2
|
18
|
1,080
|
|
1980
|
125
|
42
|
167
|
1,081
|
2
|
9
|
1,092
|
|
1981
|
147
|
66
|
213
|
1,064
|
2
|
1
|
1,067
|
|
1982
|
143
|
40
|
183
|
866
|
1
|
1
|
868
|
|
1983
|
90
|
4
|
94
|
782
|
3
|
1
|
786
|
|
1984
|
88
|
2
|
90
|
774
|
4
|
1
|
779
|
|
1985
|
91
|
1
|
92
|
777
|
5
|
1
|
783
|
|
1986
|
86
|
2
|
88
|
728
|
4
|
1
|
733
|
|
1987
|
74
|
-
|
74
|
678
|
4
|
-
|
682
|
|
1988
|
77
|
3
|
80
|
668
|
2
|
-
|
670
|
|
1989
|
75
|
2
|
77
|
673
|
3
|
-
|
676
|
|
1990
|
72
|
2
|
74
|
677
|
2
|
-
|
679
|
|
1991
|
66
|
3
|
69
|
642
|
2
|
-
|
644
|
|
1992
|
63
|
4
|
67
|
593
|
2
|
-
|
595
|
|
1993
|
60
|
2
|
62
|
595
|
2
|
-
|
597
|
|
1994
|
56
|
7
|
63
|
581
|
2
|
-
|
583
|
|
1995
|
53
|
4
|
57
|
568
|
2
|
-
|
570
|
|
1996
|
46
|
4
|
50
|
545
|
2
|
-
|
547
|
|
1997
|
46
|
2
|
48
|
540
|
2
|
-
|
542
|
|
1998
|
46
|
4
|
50
|
554
|
2
|
-
|
556
|
|
1999
|
47
|
3
|
50
|
564
|
1
|
1
|
566
|
|
2000
|
45
|
2
|
47
|
578
|
3
|
-
|
581
|
|
2001
|
42
|
2
|
44
|
540
|
2
|
-
|
542
|
|
2002
|
41
|
-
|
41
|
520
|
1
|
3
|
524
|
|
2003
|
41
|
1
|
42
|
503
|
2
|
2
|
507
|
|
2004
|
45
|
-
|
45
|
505
|
4
|
2
|
511
|
|
2005
|
44
|
1
|
45
|
503
|
5
|
2
|
510
|
|
2006
|
44
|
1
|
45
|
498
|
4
|
2
|
504
|
|
2007
|
47
|
-
|
47
|
490
|
3
|
2
|
495
|
Table
01. Number of Nonmetallic Operations in the United States,
by Primary
Activity, 1978-2007 continued:
Year
|
Total Mining
|
Indp Shops/Yrds
|
Mills
|
Total w/o Office
|
Office
|
Grand Total
|
|
1978
|
1,261
|
4
|
465
|
1,730
|
7
|
1,737
|
|
1979
|
1,192
|
4
|
430
|
1,626
|
10
|
1,636
|
|
1980
|
1,259
|
3
|
328
|
1,590
|
14
|
1,604
|
|
1981
|
1,280
|
2
|
405
|
1,687
|
19
|
1,706
|
|
1982
|
1,051
|
3
|
359
|
1,413
|
28
|
1,441
|
|
1983
|
880
|
2
|
278
|
1,160
|
15
|
1,175
|
|
1984
|
869
|
3
|
263
|
1,135
|
22
|
1,157
|
|
1985
|
875
|
4
|
257
|
1,136
|
20
|
1,156
|
|
1986
|
821
|
4
|
231
|
1,056
|
15
|
1,071
|
|
1987
|
756
|
2
|
231
|
989
|
11
|
1,000
|
|
1988
|
750
|
2
|
222
|
974
|
10
|
984
|
|
1989
|
753
|
1
|
207
|
961
|
9
|
970
|
|
1990
|
753
|
-
|
212
|
965
|
18
|
983
|
|
1991
|
713
|
-
|
194
|
907
|
12
|
919
|
|
1992
|
662
|
-
|
178
|
840
|
15
|
855
|
|
1993
|
659
|
-
|
184
|
843
|
9
|
852
|
|
1994
|
646
|
-
|
178
|
824
|
11
|
835
|
|
1995
|
627
|
-
|
176
|
803
|
6
|
809
|
|
1996
|
597
|
-
|
177
|
774
|
7
|
781
|
|
1997
|
590
|
-
|
184
|
774
|
12
|
786
|
|
1998
|
606
|
-
|
183
|
789
|
12
|
801
|
|
1999
|
616
|
-
|
179
|
795
|
13
|
808
|
|
2000
|
628
|
-
|
178
|
806
|
15
|
821
|
|
2001
|
586
|
-
|
179
|
765
|
20
|
785
|
|
2002
|
565
|
-
|
177
|
742
|
21
|
763
|
|
2003
|
549
|
-
|
169
|
718
|
16
|
734
|
|
2004
|
556
|
-
|
167
|
723
|
18
|
741
|
|
2005
|
555
|
-
|
171
|
726
|
13
|
739
|
|
2006
|
549
|
-
|
171
|
720
|
21
|
741
|
|
2007
|
542
|
-
|
163
|
705
|
20
|
725
|
|