{"Altoona city":{"population":[10382,10865,11241,11600,11959,12414,12870,13325,13766,14206,14541,15016,15740,16051,16592,17572,18102,18702,18805,19272,19503],"year":[2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020]},"Polk County":{"population":[374258,380108,384355,388277,392164,399030,405990,413024,419495,425737,430640,438783,444753,452780,461069,467517,474593,480962,486222,491031,494281],"year":[2000,2001,2002,2003,2004,2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020]}}