Year | Ever | In the past month | In the past week |
---|---|---|---|
2006 | 11% | ||
2007 | 13% | ||
2008 | 18% | 9% | |
2009 | 22% | 11% | |
2010 | 23% | 12% | |
2011 | 25% | 12% | |
2012 | 29% | 14% | |
2013 | 27% | 12% | 7% |
2014 | 30% | 15% | 8% |
2015 | 33% | 17% | 10% |
2016 | 36% | 21% | 13% |
2017 | 40% | 24% | 15% |
2018 | 44% | 26% | 17% |
2019 | 51% | 32% | 22% |