Hello and welcome to the Intelligence from the Economist. I'm your host Jason Palmer.

Every weekday we provide a fresh perspective on the events shaping your world.

One of the trickiest social norms to navigate away from home is tipping. Is this too much?

Too little? Turns out that it confounds economists too. We look into the motivations for the

tippers and for the tipped and how that affects businesses overall.

And now that the saga of Novak Djokovic's will he won't he at the Australian open has been resolved,

we take a look at why the Serbian isn't outlier among elite athletes and some surprisingly long run

affects that sports stars suffer after COVID-19. But first, net zero emissions commitments

are spilling out of businesses and even governments all the time these days. But the latest one

is kind of surprising. Exxon mobile, America's biggest oil company. It's got a pretty

checkered history on climate matters from executives that denied the role of fossil fuels and climate

change to allegations of disinformation campaigns which generations of those same executives

have denied. But now there does seem to be something of a change of heart going on.

We've seen a significant shift on climate change from the most important oil company in the

Western world, Exxon mobile. One that has actually historically been quite an opponent of

action on tackling greenhouse gas emissions. VJ, Vythe, Swarong is our global energy and climate

innovation editor. They have just announced a policy which aims to get the company to net zero

greenhouse gas emissions by 2050. But more importantly, I think they've also taken on concrete targets

for absolute levels of greenhouse gas emissions promising to cut them by roughly 20% by 2030, 30%

in their upstream operations where they make the oil and gas. So these are some concrete targets

for the first time from the company and that does represent a significant shift.

And so how to get there? What are they going to have to do to meet those numbers?

...