cd "C:\Users\Lenovo\OneDrive\写作"
drop _merge
forvalues i = 2002/2014 {
merge 1:1 var1 using "`i'"
drop _merge
}
save 2000-14.dta
cd "C:\Users\Lenovo\OneDrive\写作"
drop _merge
forvalues i = 2002/2014 {
merge 1:1 var1 using "`i'"
drop _merge
}
save 2000-14.dta