Year 1 in: rate varies by country 2000 1400 2001 1500 2002 1500 2003 1500 2004 1600 2005 2000 2006 2300 2007 2800 2008 2500 2009 2700 2010 2600 2011 3800 2012 4000 2013 4200 2014 4700 2015 4900 2016 3700 2017 4500 2018 5000 2019 5500 2020 5700