Incoming Apple CEO John Ternus faces a daunting challenge when he officially takes over from Tim Cook on Sept. 1. Bank of America analyst Wamsi Mohan has quantified the scale of that challenge with a striking figure: $32 million.

According to Mohan’s calculations, Apple’s market capitalization has grown at a rate of roughly $32 million per hour, every hour, for nearly 15 years under Cook’s leadership — a total increase of $4.5 trillion. Apple’s market cap has climbed from around $350 billion to $4.5 trillion during Cook’s tenure as CEO, according to Yahoo Finance AlphaSpace analysis.

“Tim Cook took Apple from a company driven by a small number of product cycles into an institution capable of producing growth, cash flow, customer loyalty, and innovation at enormous scale and SKU complexity,” Mohan said.

An Era Ends, A New One Begins

On April 20, Apple announced that Cook would step down after nearly 15 years at the helm, handing the reins to Ternus, Apple’s senior vice president of hardware engineering. The transition, which takes effect on Sept. 1, marks only the second CEO change in Apple’s history since co-founder Steve Jobs handed the keys to Cook in August 2011, shortly before Jobs’s death.

Cook, who joined Apple in 1998 as an executive vice president of worldwide sales and operations when the company was near bankruptcy, oversaw one of the greatest corporate transformations in American history. Revenue has nearly quadrupled under his watch, climbing to over $400 billion annually, as he shepherded the launch of the Apple Watch, AirPods, and the Vision Pro headset. He also became an industry statesman and forged a solid working relationship with President Trump over Trump’s two terms.

What Lies Ahead for Ternus

Cook has described Ternus as having “the mind of an engineer, the soul of an innovator, and the heart to lead with integrity and honor” — traits the 51-year-old will need to navigate Apple’s future in the era of AI.

Ternus officially takes over ahead of key product launches and the all-important holiday shopping period. But the challenge extends beyond managing product cycles. “Apple is already so large, profitable, and deeply embedded in its customers’ lives that incremental excellence may no longer be enough to redefine the company,” Mohan said. “Ternus’s challenge will be to preserve the profitable machine Cook built while restoring a stronger sense of technological surprise”.