Year % of total working-age population with basic education 2005 40.471 2006 41.296 2007 41.476 2008 42.314 2009 41.075 2010 39.488 2011 39.99 2012 37.969 2013 38.562 2014 39.785 2015 37.988 2016 34.913 2017 33.45 2018 33.315 2019 33.608 2020 31.663 2021 29.848 2022 28.157