"Despite the steady melt-up in Apple shares over the past few months, there has actually been a steady drumbeat of bad news," an analyst said Tuesday.

A 30% gain over the course of a single year is a tough act to follow, particularly when it follows a 46% advance from the year before. There's seemingly little room left for yet another year of similar gains. This is Apple though, and an Apple with more prospective growth drivers at its disposal than it's had in several years.

MoffettNathanson co-founder and senior analyst Craig Moffett explains why his firm has downgraded its rating and target price for Apple. Craig speaks with Tom Keene and Paul Sweeney on Bloomberg Radio.

An analyst says Apple’s stock price bakes in only good news, but he sees more than 20% downside as negative developments pile up.