Add event tracking to Ninja Forms submit

gistfile1.phtml

add_action( 'ninja_forms_display_js', 'prefix_track_form_submission' );
function prefix_track_form_submission() {
    ?>
    
    <script>
    //<![CDATA[
        $( '.ninja-forms-form' ).on( 'submitResponse', function( e, response ) {
            var errors = response.errors;
            if ( errors == false ) {
                // This is where you put the tracking code. This only fires if form submission is successfull
                _gaq.push(['_trackEvent', 'Contact Form-Send', 'Click']);
            }
        });
    //]]>
    </script>
    
    <?php
}