Elo with question mark(?),what is this?

I see that my elos in horde and in 3 check is with (?),during game in section-Playing right now,
What is this?

I think it's because you doesn't play a game recently of they variants or you doesn't have more than 30 game in they variants.

Other topic : http://fr.lichess.org/forum/lichess-feedback/question-marks#6

http://en.lichess.org/qa/342/what-does-a-question-mark--next-to-my-rating-mean