#15. Pinal County

- Median year homes built: 2003
- Homes built 1939 or earlier: 0.9% (1,701 homes)
- Homes built since 2000: 3.4% (6,047 homes)
- Total homes built: 179,861

#14. Mohave County

- Median year homes built: 1994
- Homes built 1939 or earlier: 0.5% (549 homes)
- Homes built since 2000: 1.3% (1,545 homes)
- Total homes built: 119,593

#13. Yuma County

- Median year homes built: 1994
- Homes built 1939 or earlier: 1.5% (1,372 homes)
- Homes built since 2000: 1.0% (951 homes)
- Total homes built: 93,924

#12. Yavapai County

- Median year homes built: 1994
- Homes built 1939 or earlier: 2.4% (3,018 homes)
- Homes built since 2000: 2.0% (2,429 homes)
- Total homes built: 124,032

#11. Maricopa County

- Median year homes built: 1992
- Homes built 1939 or earlier: 0.9% (16,708 homes)
- Homes built since 2000: 1.7% (32,353 homes)
- Total homes built: 1,850,862

#10. Coconino County

- Median year homes built: 1990
- Homes built 1939 or earlier: 1.7% (1,162 homes)
- Homes built since 2000: 1.0% (721 homes)
- Total homes built: 69,907

#9. Santa Cruz County

- Median year homes built: 1990
- Homes built 1939 or earlier: 4.0% (759 homes)
- Homes built since 2000: 0.7% (142 homes)
- Total homes built: 18,997

#8. Apache County

- Median year homes built: 1988
- Homes built 1939 or earlier: 0.9% (265 homes)
- Homes built since 2000: 0.6% (160 homes)
- Total homes built: 29,001

#7. Navajo County

- Median year homes built: 1988
- Homes built 1939 or earlier: 2.9% (1,669 homes)
- Homes built since 2000: 0.6% (333 homes)
- Total homes built: 56,946

#6. Graham County

- Median year homes built: 1987
- Homes built 1939 or earlier: 5.7% (791 homes)
- Homes built since 2000: 1.6% (220 homes)
- Total homes built: 13,941

#5. La Paz County

- Median year homes built: 1986
- Homes built 1939 or earlier: 0.8% (111 homes)
- Homes built since 2000: 0.3% (38 homes)
- Total homes built: 13,653

#4. Pima County

- Median year homes built: 1986
- Homes built 1939 or earlier: 1.9% (9,035 homes)
- Homes built since 2000: 1.2% (5,537 homes)
- Total homes built: 475,378

#3. Cochise County

- Median year homes built: 1986
- Homes built 1939 or earlier: 6.9% (4,100 homes)
- Homes built since 2000: 0.4% (253 homes)
- Total homes built: 59,312

#2. Gila County

- Median year homes built: 1985
- Homes built 1939 or earlier: 5.8% (1,888 homes)
- Homes built since 2000: 0.9% (285 homes)
- Total homes built: 32,614

#1. Greenlee County

- Median year homes built: 1981
- Homes built 1939 or earlier: 4.0% (175 homes)
- Homes built since 2000: 0.3% (15 homes)
- Total homes built: 4,422