At the same time, the midrange Apple iPhone 5c commanded 27% of the iPhone market in Q4 of 2013. That was lower than the 32% owned by the then midrange Apple iPhone 4s during the same time period in 2012. The reasoning seems convoluted, but the thought here is that the iPhone 5c did a better job in migrating iPhone buyers to the higher priced iPhone 5s. And buyers seem willing to spend the extra money to buy the iPhone 5s variants with more storage capacity.
CIRP analyst Josh Lowitz pointed out that since the average price of iPhones purchased in 2013 rose, Apple's strategy worked. And when asked a hypothetical question about what would have happened had Apple kept the iPhone 5 as its midrange model Lowitz concludes that it would have outsold the iPhone 5c since midrange legacy Apple iPhones have historically sold well. All in all, the stats all seem to have the same conclusion, which is that the Apple iPhone 5c has forced buyers to move up to the Apple iPhone 5s.
source: re/code via BGR