This is from the Statistical Abstract of the United States: 1998, page 8. What happened to the states of the union? Did they disappear after 1960?

Population

No. 1 Population and Area: 1790 to 1900

CENSUS DATE Number Per square mile Number increase Percent increase Total Land Water
CONTERMINOUS
U.S.
1790 (Aug. 2)
1800 (Aug. 4)
1810 (Aug. 6)
1820 (Aug. 7)
1830 (June 1)
1840 (June 1)
1850 (June 1)
1860 (June 1)
1870 (June 1)
1880 (June 1 )
1890 (June 1)
1900 (June 1)
1910 (Apr. 15)
1920 (Jan. 1)
1930 (Apr. 1)
1940 (Apr. 1)
1950 (Apr. 1)
1960 (Apr. 1)

3,929,214
5,308,483
7,239,881
9,638,453
12,866,020
17,069,453
23,191,876
31,443,321
39,818,449
50,155,783
62,947,714
75,994,575
91,972,266
105,710,620
122,775,046
131,669,275
150,697,361
178,464,236

4.5
6.1
4.3
5.5
7.4
9.8
7.9
10.6
13.4
16.9
21.2
25.6
31.0
35.6
41.2
44.2
50.7
60.1

(X)
1,379,269
1,931,398
2,398,572
3,227,567
4,203,433
6,122,423
8,251,445
8,375,128
10,337,334
12,791,931
13,046,861
15,977,691
13,738,354
17,064,426
8,894,229
19,028,086
27,766,875

(X)
35.1
36.4
33.1
33.5
32.7
35.9
35.6
26.6
26.0
25.5
20.7
21.0
14.9
16.1
7.2
14.5
18.4

891,364
891,364
1,722,685
1,792,552
1,792,552
1,792,552
2,991,655
3,031,295
3,021,295
3,021,295
3,021,295
3,021,295
3,021,295
3,021,295
3,021,295
3,021,295
3,021,295
3,021,295

864,746
864,746
1,681,828
1,749,462
1,749,462
1,749,462
2,940,042
2,969,640
2,969,640
2,969,640
2,969,640
2,969,834
2,969,565
2,969,451
2,977,128
2,977,128
2,974,726
2,968,054

24,065
24,065
34,175
38,544
38,544
38,544
52,705
52,747
52,747
52,747
52,747
52,553
52,822
52,936
45,259
45,259
47,661
54,207
UNITED STATES
1950 (Apr. 1)
1960 (Apr. 1)
1970 (Apr. 1)
1980 (Apr. 1)
1990 (Apr. 1)
151,325,798
179,323,175
203,302,031
226,542,199
248,718,301
42.6
50.6
57.4
64.0
70.3
19,161,229
27,997,377
23,978,856
23,240,168
22,176,102
14.5
18.5
13.4
11.4
9.8
3,618,770
3,618,770
3,618,770
3,618,770
3,717,796
3,552,206
3,540,911
3,540,023
3,539,289
3,536,278
63,005
74,212
78,444
79,481
181,518
CONTERMINOUS U.S. excludes Alaska and Hawaii
Source: U.S. Bureau of the Census, 1990 Census of Population and Housing, Population and Housing Unit Counts (CPH-2);
1990 Census of Population and Housing Listing (1990 CPH-L-157); and unpublished data.
from: Statistical Abstracts of the United States 1998, Sep. 16, 1998.

Conterminious. - Black's 6th

Adjacent; adjoining; having a common boundary; coterminous.