This paper looks at how wealth and income inequality change during economic ups and downs, and how they are linked to shifts in how money is distributed. The researchers studied data from OECD countries between 1970 and 2016 and found that income inequality tends to go down when the economy is doing well. They also discovered that changes in how much capital owners get can affect inequality. By using a model that simulates different scenarios, they found that productivity changes can initially increase inequality but then decrease it over time. In the US, productivity shocks explain about 17% of the ups and downs in inequality.