AccordingtoNielsen,theaveragenumberofmobilephonecalls...
问题详情： AccordingtoNielsen,theaveragenumberofmobilephonecallswemakeisdroppingeveryyear,afterhittingapeakin2007.Andourcallsaregettingshorter:In2005theyaveragedthreeminutesinlength;nowthey’realmost...