Region
United States
4,406
Colorado
474
California
73
Canada
59
Alaska
54
Australia
42
New Mexico
40
Oregon
38
Washington (State)
38
Texas
32
Florida
30
Wyoming
29
Pennsylvania
27
Washington (D.C.)
25
Arizona
24
New York (State)
24
West (U.S.)
24
Kansas
23
Utah
23
Hawaii
22
Illinois
20
Kentucky
20
Maryland
20
Ohio
20
Missouri
18
Montana
17
Northeastern States
17
Virginia
17
Mississippi
16
Nevada
16
North Dakota
16
Ontario
16
Atlantic Coast (U.S.)
15
Idaho
15
Southern States
15
Tennessee
15
China
14
Georgia
14
Massachusetts
14
New Jersey
14
North America
14
Indiana
13
Nebraska
13
North Carolina
13
Colorado River Watershed (Colo.-Mexico)
12
Middle West
12
South Carolina
12
Louisiana
11
Foreign countries
10
Gulf Coast (U.S.)
10
more ...