本人Stata新手，遇到一个问题请教大神
// 2. Calculate the unemployment rate.
foreach i of varlist employment {
  foreach j of varlist unemployment{
   gen unemrate = j / (j+i)
}
}
用这个代码会提示j not found

// 2. Calculate the unemployment rate.
foreach i of varlist employment {
  foreach j of varlist unemployment{
   gen unemrate = unemployment/ (employment+unemployment)
}
}
用这个就能正确运行，但是觉得i和j没有用到，想知道怎么更改，