Year Percent Change From Preceding Period 2004-01-01 8.95689891214052 2005-01-01 7.67194447689967 2006-01-01 10.13343738079350 2007-01-01 7.58803792872552 2008-01-01 12.00230711584230 2009-01-01 7.87724306162193 2010-01-01 7.62066545521830 2011-01-01 8.68500214660450 2012-01-01 8.56577176825493 2013-01-01 8.98710309462170 2014-01-01 8.87767229540653 2015-01-01 -2.95848106493362 2016-01-01 -2.53325991865928 2017-01-01 -3.29308073061939 2018-01-01 2.04899999999991 2019-01-01 3.04900000000003