What percentage of these cars came with a stick shift?

I noticed a for sale ad for a 1996 Mustang, and was struck by the $3500 price… ’94-‘04 Mustangs seem like a great bang for the buck:  They are cheap, plentiful, have lots of parts available, and there’s lots of online DIY support.  Perfect for a student or hobbyist on a budget.

I opened up 35 ads and noticed 19 were manual.     I realized I was staring at a confidence interval problem!