In our recent "Infinite Dial" presentation in conjunction with Arbitron, we showed the graph above, which says what percentage of the users of any given item said it has a 'big impact' on their lives. Now before anyone says I'm bashing radio, let me stress that this graph went on for two pages and many items scored lower than AM/FM radio in terms of impact. And 22% of users of a product saying it has a big impact on their lives is formidable. Since radio is used by such a large portion of the population, that means a very significant portion of all Americans consider radio are saying that radio really is important to them.So who are these people? Well, intriguingly, almost every age group gave radio the same score on this scale. So the portion of each age group saying radio has a big impact upon them is about the same.The 'radio big impact' people are disproportionately black and hispanic, and disproportionately lower education (these are related factors).Over the next few days I'll follow with more analysis of this fifth of the US population that says radio has a 'big impact' on their lives. But it is important for us all to remember that indeed, radio does have a real impact on the lives of many, many people. Let's explore who they are now, and how radio can continue to have such an impact going forward.