tracking form submissions with google analytics

hi all,
as specified here
https://contactform7.com/tracking-form-submissions-with-google-analytics/

i have added the code for tracking form submissions with google analytics
so:
on_sent_ok: “_gaq.push([‘_trackevent’, ‘contact form’, ‘submit’]);”

but is there something else i have to set up in analytics?
is there any guide please as the code is not tracking anything (checked 48hours afet a form submission).

thanks

https://www.ads-software.com/plugins/contact-form-7/

[ No bumping please. ]