Help Using CountIf Function?

[Jason Browen]

Dear all,

I am using Stata 16, on mac. I have taken a snapshot on the panel dataset I am working with.
I used the following code:
generate mlda_21 = 0 if mlda<21
replace mlda_21 = 1 if mlda==21

to create the dummy variable mlda_21 which equals 0 if the minimum drinking age is less than 21 and equals 1 if the minimum drinking age is = to 21
I want to see how many states have a mlda of 21 for the year 1982. I was thinking of using the CountIf function?

Thank you in advance for your help

Jason Browen

[Nick Cox]

Please read https://www.statalist.org/forums/help#stata on why screenshots are not as helpful as you hope.

Otherwise I am not aware of a CountIf function: this isn't MS Excel. But yes, there is a count command, so try

count if year == 1982 & mlda == 21

https://www.stata.com/support/faqs/d...rue-and-false/ shows that

generate mlda_21 = mida == 21 if mida < .

is a one-line alternative to your two statements.

[Jason Browen]

Thank you so very much Nick! It works great!