It would be helpful if you actually posted the study, not a quantitative graph without context of the data contained within. It is misleading.

The study: https://www.pnas.org/content/107/38/16489

"Emotional well-being also rises with log income, but there is no further progress beyond an annual income of ~$75,000"

"We conclude that high income buys life satisfaction but not happiness, and that low income is associated both with low life evaluation and low emotional well-being."

The study states that emotional well-being does not rise with income over 75k. The study also concludes that high income is not correlated to happiness.

These conclusions are clearly erroneous.