Tim Cook, who marked his five-year anniversary as Apple's chief executive officer on Wednesday, received shares valued at $373 million (€330 million) during that period as the iPhone maker's stock doubled on his watch.

When Mr Cook took the helm in 2011, he was granted 1 million shares. Originally, 50 per cent of those were scheduled to vest on his five-year anniversary, with the rest coming due after a decade with the company. That changed in 2013, when Cook voluntarily tied one-third of the award to outperforming the S&P 500 Index and the shares began vesting annually.

That hasn’t slowed him down much. He’s received 98.6 per cent of the units available to him in his first five years, according to data compiled by Bloomberg. Those were valued at $373 million at Wednesday’s close - and he can still earn the same number of shares over the next half decade.

Mr Cook's payout is based on Apple returning 61 per cent during the past three years, placing it in the top-performing third of the S&P index, according to data compiled by Bloomberg.

Mr Cook would get all of his shares for 2016 under those terms. He’s earned 3.45 million shares under the plan when accounting for a 7-for-1 stock split in 2014.

Apple spokesman Josh Rosenstock declined to comment, and referred to a January 6 proxy statement on Mr Cook's share awards. The stock closed at $108.03 Wednesday in New York, up from a split- adjusted $53.74 on the day Mr Cook took over the top job.

Mr Cook has used buybacks and dividend increases to help ensure that Apple stock outperformed the S&P 500 even as sales slowed.

In 2013, he extended a share-buyback programme sixfold ahead of the introduction of the iPhone 6 the following year, which reignited growth.

Bloomberg