Data from Consumer Intelligence Research Partners shows that iPhone owners are holding onto their phones longer before they upgrade them. Three years ago, almost two-thirds of iPhones in use were just 1-2 years old, but CIRP says that number has now fallen to just 51%.

CIRP attributes the change to a combination of the slowing pace of development and carriers switching from phone-inclusive plans to separate financing for the phone itself …

It’s this phenomenon that led Apple to launch an iPhone upgrade program intended to encourage frequent upgrades.

Only a few years ago, mobile carrier phone purchase subsidies encouraged customers to upgrade a phone on a steady two-year cycle with no monthly discount for holding a new phone beyond two years. Today, phone financing plans effectively reward customers who have paid for their phone in full. This motivator appears to outweigh the impact of any early upgrade options that carriers offer with the new financing plans

CIRP suggests that the only compelling new features can persuade users to revert to more frequent upgrading, something which appears to be in some doubt. Others, however, see similar data as a reason for optimism.

CIRP’s latest data is based on a survey of 2,767 Apple customers in the USA.