iPhone Upgrade: By the Numbers

From: iPhone XS Max purchased for $1,099.00 on December 15, 2018
To: iPhone 16e for $699.00 on August 15, 2025
Trade-in value: $110.00 (effective cash out: $589.00)

Ownership Metrics

Metric	Value
Days owned	2,435 days
Years owned (approx)	6.67 years
Months owned (avg month length)	80.0 months
Net cost of ownership	$989.00
Cost per day	$0.41 / day
Cost per month (avg)	$12.36 / month
Value retained at trade-in	10.01%
Total depreciation	89.99%
Annualized depreciation (CAGR)	-29.20% per year

Quick Takes

Every day with the XS Max cost about $0.41 after trade-in.
Over roughly 6.67 years, it lost about 90.0% of its value, keeping ~10.0%.
Upgrade day out-of-pocket for the 16e: $589.00.

Notes: Months use the average Gregorian month length (30.436875 days). Annualized depreciation uses start/end values over actual days held.