The answer to this sort of depends. There are some people who just don't stay in touch with anyone, and so if you want to talk you HAVE to call them. My best friend when I was teen was like that... he NEVER called anyone but was happy to get calls. No, it didn't make sense.

But most people will call or email/message you if they're interested in maintaining a friendship. Especially since you say you only talk to these people like once a year... I wouldn't consider that a real friendship. There would have to be too much going on in both your lives that the other didn't know about for it to be a relationship with any real closeness. So you're probably better off forming friendships with people who have more time and desire to talk with you.