| Characteristic | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| - | - | - | - | - | - | - | - | - | - | - | - |
| - | - | - | - | - | - | - | - | - | - | - | - |
| - | - | - | - | - | - | - | - | - | - | - | - |
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Sources
Release date
August 2019
Region
United States
Survey time period
2008 to 2018
Supplementary notes
Content prior to 2013 is taken from an older edition of the report
Citation formats









