Hayes was recorded as the eighth highest-earning caddie according to Forbes by the end of 2017 receiving a reported $520,000, a year in which Rahm won once on the PGA Tour. That figure doesn't likely include the DP World Tour where Rahm also won and twice including the Tour Championship.
Rahm topped the money list in 2021 with earnings of £7.7m so a nice percentage of that will all add up – the US Open victory alone was good for $2.25m so 10 per cent means Hayes will have collected around $220,000 for his week's work at Torrey Pines.