Mobile phone penetration in the US will hit 84 percent by the end of this year 100 percent in 2013 predicts SNL Kagan (note that penetration does not equate to the proportion of people with mobile phones, since there will be a number of people with more than one phone account)... it has already passed 100 percent in several countries. ARPU is predicted to grow at an inflation-adjusted 1.5 percent per year over the next 10 years, from $52.38 today to $61.09 by 2017 reports GigaOM. There is some disagreement between SNL Kagan and Chetan Sharma over what proportion of ARPU is due to data, but it’s clear it will be growing at a far greater rate than overall ARPU, which means the voice segment will be declining…