| Characteristic | 2012 | 2013 | 2014 | 2015 | 2016 |
|---|---|---|---|---|---|
| - | - | - | - | - | - |
| - | - | - | - | - | - |
| - | - | - | - | - | - |
| - | - | - | - | - | - |
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Sources
Release date
March 2017
Region
United States
Survey time period
2012 to 2016
Supplementary notes
* June 2015 to May 2016
Figures prior to 2016 were taken from previous annual reports.
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