The iPhone installed base is currently worth an estimated $147 billion.

CEO Tim Cook holding the billionth iPhone. (Photo: Apple)

With Appleshares trading at all-time highs and briefly flirting with $400, Morgan Stanley analyst Katy Huberty reiterated her outperform rating and boosted the firm’s price target from $340 to $419 on Monday. While Apple’s iPhone trade-in program isn’t new by any stretch, Huberty has crunched some numbers and argues that the offering is a “sustainable competitive advantage” that could be underappreciated by investors.

In fact, the program could help fund a meaningful portion of upgrades for years.

Trade-ins have become an important way for Apple to remove friction around the upgrade process while offsetting part of rising prices.

The iPhone installed base of over 900 million is worth