请问我的平行趋势事前检验通过吗？
代码如下：

keep yeartreatment lnNOX

savea_data,replace

keep iftreatment==1

bysort year: egentreated=mean(lnNOX)  

rename treated 处理组

duplicates dropyear,force

keep year 处理组

savea_part1,replace

use a_data,clear

keep iftreatment==0

bysort year: egencontrol=mean(lnNOX)

rename control 控制组

duplicates dropyear,force

keep year 控制组  

merge 1:1 yearusing a_part1  

save a,replace

rename year 年份

twoway(connect 处理组 年份, lcolor(black) msymbol(none)) (connect 控制组 年份,msymbol(none) lcolor(black) lpattern(dash)),xlabel(2015(1)2021)ylabel(8(1)12)xline(2018, lcolor(black) lpattern(dash)) xtitle("年份") ytitle("lnNOX") scheme(s1mono)