Count number of items in a multiselect list

Hello Sugar Club,

In the Opportunities module, I have a multiselect field for Lead Services. I'd like to start tracking the number of services our sales team is pitching to each prospect and thought I could do it with a calculated field by using the formula Count($services). When I test out this formula after selecting 2 services in the multi select field, Sugar is calculating 0 in the number of services field. 

Is there another formula I should be using in the calculated field section?