Among those three platforms this year, Instagram is the only one where the split of new users over the age of 35 vs. under 35 will be nearly 50-50. Instagram will add just more than 12 million new users this year, which is more than double any other social network. And while Facebook, Snapchat and Instagram all have a 'Stories' feature, it’s Instagram Stories that will be especially successful in capturing new sign-ups. For the most part, Instagram's user base skews younger, with millennials making up the largest share and representing nearly half of the platform's US user base this year. Get the full story at eMarketer