The shooting of Trayvon Martin has focused national attention on Florida’s so-called Stand Your Ground law, under which a person claiming self-defense can justify killing an alleged assailant.

Because Trayvon was killed by George Zimmerman’s 9mm semi-automatic handgun, we wondered how the gun-ownership rates have changed since our 2010 report, in which we crunched the numbers to find out which states (including Washington, D.C.) are the most armed.

For our updated ranking, we considered state data from the FBI’s National Instant Criminal Background Check System for the last 18 months. We divided the number of background checks by each state’s population to come up with our final ranking.

A point of caution: states are not consistent in reporting NICS data. Some use the system for background checks on purchases on the secondary market and others do not. Also, Kentucky implemented monthly NICS checks on concealed weapons, which inflates its numbers.

1. Kentucky

NICS background checks per 100,000 residents (Sept. 2010 – Feb. 2012): 78,703

Previous rank: 1^st

2. Utah

NICS background checks per 100,000 residents: 46,898

Previous rank: 2^nd

3. Montana

NICS background checks per 100,000 residents: 16,888

Previous rank: 3^rd

4. West Virginia

NICS background checks per 100,000 residents: 15,718

Previous rank: 6^th

5. Alaska

NICS background checks per 100,000 residents: 14,616

Previous rank: 5^th

6. Wyoming

NICS background checks per 100,000 residents: 13,986

Previous rank: 4^th

7. North Dakota

NICS background checks per 100,000 residents: 13,952

Previous rank: 8^th

8. South Dakota

NICS background checks per 100,000 residents: 13,624

Previous rank: 7^th

9. Oklahoma

NICS background checks per 100,000 residents: 11,279

Previous rank: 12^th

10. Arkansas

NICS background checks per 100,000 residents: 11,150

Previous rank: 9^th

11. Alabama

NICS background checks per 100,000 residents: 11,070

Previous rank: 10^th

12. Tennessee

NICS background checks per 100,000 residents: 10,889

Previous rank: 11^th

13. New Hampshire

NICS background checks per 100,000 residents: 10,557

Previous rank: 16^th

14. Idaho

NICS background checks per 100,000 residents: 10,261

Previous rank: 13^th

15. Missouri

NICS background checks per 100,000 residents: 10,228

Previous rank: 15^th

16. Colorado

NICS background checks per 100,000 residents: 10,208

Previous rank: 14^th

17. Mississippi

NICS background checks per 100,000 residents: 10,035

Previous rank: 17^th

18. Illinois

NICS background checks per 100,000 residents: 9,831

Previous rank: 18^th

19. Minnesota

NICS background checks per 100,000 residents: 9,730

Previous rank: 22^nd

20. Louisiana

Population: 4,533,372

Previous rank: 21^st

21. Kansas

NICS background checks per 100,000 residents: 9,176

Previous rank: 23^rd

22. Washington

NICS background checks per 100,000 residents: 8,785

Previous rank: 24^th

23. Pennsylvania

NICS background checks per 100,000 residents: 8,781

Previous rank: 25^th

24. Indiana

NICS background checks per 100,000 residents: 8,691

Previous rank: 27^th

25. Wisconsin

NICS background checks per 100,000 residents: 8,676

Previous rank: 38^th

26. Maine

NICS background checks per 100,000 residents: 8,629

Previous rank: 29^th

27. New Mexico

NICS background checks per 100,000 residents: 8,589

Previous rank: 20^th

28. Iowa

NICS background checks per 100,000 residents: 8,524

Previous rank: 31^st

29. Oregon

NICS background checks per 100,000 residents: 8,287

Previous rank: 26^th

30. Connecticut

NICS background checks per 100,000 residents: 7,906

Previous rank: 19^th

31. South Carolina

NICS background checks per 100,000 residents: 7,765

Previous rank: 28^th

32. Texas

NICS background checks per 100,000 residents: 7,060

Previous rank: 33^rd

33. Vermont

NICS background checks per 100,000 residents: 6,728

Previous rank: 35^th

34. Nevada

NICS background checks per 100,000 residents: 6,583

Previous rank: 32^nd

35. Virginia

NICS background checks per 100,000 residents: 6,387

Previous rank: 30^th

36. Ohio

NICS background checks per 100,000 residents: 6,274

Previous rank: 39^th

37. North Carolina

NICS background checks per 100,000 residents: 6,178

Previous rank: 34^th

38. Georgia

NICS background checks per 100,000 residents: 5,934

Previous rank: 36^th

39. Arizona

NICS background checks per 100,000 residents: 5,934

Previous rank: 41^st

40. Nebraska

NICS background checks per 100,000 residents: 5,758

Previous rank: 40^th

41. Michigan

NICS background checks per 100,000 residents: 5,596

Previous rank: 37^th

42. Florida

NICS background checks per 100,000 residents: 5,212

Previous rank: 42^nd

43. Delaware

NICS background checks per 100,000 residents: 3,876

Previous rank: 43^rd

44. California

NICS background checks per 100,000 residents: 3,611

Previous rank: 44^th

45. Massachusetts

NICS background checks per 100,000 residents: 3,500

Previous rank: 46^th

46. Maryland

NICS background checks per 100,000 residents: 2,738

Previous rank: 45^th

47. Rhode Island

NICS background checks per 100,000 residents: 2,496

Previous rank: 47^th

48. New York

NICS background checks per 100,000 residents: 2,172

Previous rank: 48^th

49. Hawaii

NICS background checks per 100,000 residents: 1,359

Previous rank: 49^th

50. New Jersey

NICS background checks per 100,000 residents: 1,030

Previous rank: 50^th

51. District of Columbia

NICS background checks per 100,000 residents: 81

Previous rank: 51^st

^{http://www.thedailybeast.com/articles/2012/03/21/states-with-the-most-guns-in-2012.print.html}