*** SIMULATED DATA ***
. clear
. set obs 5
. set seed 10101
. gen id=_n
. expand 50
. drop in 1/5
. bys id: gen time=_n+1999
. gen D=rbinomial(1,0.4)
. gen x1=rnormal(1,7)
. tsset id time
  forvalues i=1/6{
  gen L`i'_x=L`i'.x
  }
. bys id: gen y0=5+1*x+ rnormal()
. bys id: gen y1=100+5*x+90*L1_x+90*L2_x+120*L3_x+100*L4_x+90*L5_x +90*L6_x + rnormal()
. gen A=6*x+rnormal()
. replace D=1 if A>=15
. replace D=0 if A<15
. gen y=y0+D*(y1-y0)
. tsset id time
. xi: ddid y D x , model(fe) pre(6) post(6) vce(robust) graph save_graph(mygraph)