California counties top the list of the most economically stressed counties in the nation, according to an Associated Press Economic Stress Index that was released on Monday.

Seven of the Top 10 most stressed counties are in California. Imperial County and Merced County ranked at No. 1 and No. 2, respectively, on the list.

The index calculates a score from 1 to 100 based on a county’s unemployment, foreclosure and bankruptcy rates from Dec. 2009, according to the Associated Press.

The report indicates that the higher the score, the more economic stress. The news service considers a stressed county when the score exceeds 11. The report includes only counties with populations of 25,000 or more.

No California counties made the Top 20 list of the least stressed counties (see below).

The Most Stressed Counties

1. Imperial County, Calif., 31.57
2. Merced County, Calif., 26.44

3. Lyon County, Nev., 24.93
4. San Benito County, Calif., 24.46
5. Sutter County, Calif., 24.13
6. Yuba County, Calif., 24.11
7. Stanislaus County, Calif., 23.92
8. San Joaquin County, Calif., 23.57

9. Lapeer County, Mich., 23.1
10. Marion County, S.C., 22.93
11. Nye County, Nev., 22.9
12. Chester County, S.C., 22.87
13. Clark County, Nev., 22.78
14. Lake County, Calif., 22.65
15. Lauderdale County, Tenn., 22.48
16. Union County, S.C., 22.26
17. Sanilac County, Mich., 21.71
18. Riverside County, Calif., 21.67
19. Iosco County, Mich., 21.6
20. Marshal County, Tenn., 21.53

The Least Stressed Counties

1. Ellis County, Kan., 3.5
2. Ford County, Kan., 3.78
3. Riley County, Kan., 3.85
4. Buffalo County, Neb., 4.08
5. Brookings County, S.D., 4.09
6. Brown County, S.D., 4.13
7. Finney County, S.D., 4.17
8. Ward County, N.D., 4.44
9. Clay County, Minn., 4.48
10. Grand Forks County, N.D., 4.53
11. Burleigh County, N.D., 4.6
12. Madison County, Neb., 4.73
13. Arlington County, Va., 4.73
14. Platte County, Neb., 4.8
15. Lincoln County, S.D. 4.94
16. Sioux County, Iowa, 4.97
17. Albany County, Wyo., 4.97
18. Johnson County, Iowa, 5.01
19. Monongalia County, W.Va., 5.11
20. Lancaster County, Neb., 5.2