http://www.migrationinformation.org/ has been crawled 503 times going all the way back to May 27, 2002.

A crawl can be a duplicate of the last one. It happens about 25% of the time across 420,000,000 websites. FAQ

Jan
1
2
3
4
5
6

January 7, 2011

1 snapshot

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Feb

February 1, 2011

1 snapshot

1
2
3
4
5
6
7

February 8, 2011

1 snapshot

8
9
10
11
12
13
14
15
16
17
18
19

February 20, 2011

1 snapshot

20
21
22
23
24

February 25, 2011

1 snapshot

25
26
27
28
Mar
1
2
3

March 4, 2011

1 snapshot

4
5
6

March 7, 2011

1 snapshot

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Apr
1
2
3
4
5
6
7
8
9
10
11
12
13

April 14, 2011

1 snapshot

14
15
16
17
18
19
20
21
22

April 23, 2011

1 snapshot

23
24
25

April 26, 2011

1 snapshot

26
27
28
29
30
May
1
2
3
4

May 5, 2011

1 snapshot

5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21

May 22, 2011

1 snapshot

22
23
24
25
26
27
28
29
30
31
Jun
1

June 2, 2011

1 snapshot

2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

June 24, 2011

1 snapshot

24
25
26
27
28
29
30
Jul
1
2
3
4
5
6

July 7, 2011

1 snapshot

7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Aug
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Sep
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Oct
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Nov
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Dec
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31

Note

This calendar view maps the number of times http://www.migrationinformation.org/ was crawled by the Wayback Machine, not how many times the site was actually updated. More info in the FAQ.