Digital audio listening is continuing to reach record levels each year, with now an estimated 192 million in the US alone listening every month. Just for the record – that’s 68% of the total population 12 years old or older. And with so much listening, there is bound to be audio advertising as a way to monetize the thirst for eardrum-oriented content. And there is: the first half of 2019 saw digital audio advertising revenue reach $1.2 billion, a 30.1% increase over the same period a year before