1year,n_days,mean_yield,mean_change_bp22010,250,2.4797,-0.136532011,249,2.0563,-0.457842012,250,1.38,0.04452013,250,1.622,0.22862014,250,1.5796,-0.24472015,250,0.8532,-0.24482016,250,0.7263,0.15292017,249,1.3633,0.3012102018,250,2.1513,0.008112019,250,1.5344,-0.0812