Hi everyone

I am trying to run a logit regression: logit employed firmsize

and I receive this error:
outcome does not vary; remember:
0 = negative outcome,
all other nonmissing values = positive outcome

I dropped the missing values in my independent variable (firmsize) using the code: drop if firmsize== .

but I am still receiving this error. Does anyone know how I can fix this?

Thank you in advance

Code:
* Example generated by -dataex-. For more info, type help dataex
clear
input float employed int firmsize
1 4
1 2
1 4
1 2
1 4
1 4
1 3
1 2
1 1
1 2
1 3
1 4
1 4
1 4
1 1
1 4
1 2
1 4
1 1
1 1
1 4
1 4
1 2
1 3
1 4
1 4
1 4
1 4
1 3
1 2
1 4
1 3
1 2
1 4
1 1
1 4
1 4
1 4
1 4
1 4
1 4
1 4
1 2
1 1
1 4
1 3
1 3
1 2
1 1
1 4
1 2
1 4
1 4
1 1
1 4
1 4
1 1
1 1
1 1
1 4
1 4
1 4
1 4
1 4
1 1
1 2
1 3
1 1
1 4
1 4
1 4
1 4
1 3
1 4
1 3
1 4
1 4
1 4
1 1
1 4
1 2
1 3
1 4
1 4
1 1
1 4
1 4
1 4
1 4
1 4
1 4
1 2
1 4
1 3
1 4
1 4
1 4
1 1
1 4
1 4
end
label values firmsize firmsize
label def firmsize 1 "Less than 20 employees", modify
label def firmsize 2 "20 to 99 employees", modify
label def firmsize 3 "100 to 500 employees", modify
label def firmsize 4 "More than 500 employees", modify