代码
graph twoway (connect mean_y year if treat==l,sort)(connect mean_y year if treat==0,sort lpattern(dash)), xline(2016,lpattern(dash) lcolor(gray)) ytitle("y")xtitle("年度") ylabel(,labsize(*0.75))xlabel(,labsize(*0.75))  legend(label(1 "处理组") label( 2 "控制组"))xlabel(2011 (1) 2022) graphregion(color(white))
图形