As of the end of Q4 2006, there were over 100 mln WCDMA subscribers around the world, ABI Research says. The WCDMA subscriber sector is moving particularly fast, growing 102% YTY and 16.6% QTQ. 3G subscribers are providing a much-needed shot in the arm for mobile operators, because they deliver an average revenue per user (ARPU) that is 5% to 20%% greater than the average. For many operators, the period Q2 2004 to Q2 2006 proved challenging, as competition pushed down on ARPU but the additional revenue streams from non-voice applications failed to compensate.