https://phys.org/news/2018-10-loss-productivity-world.html

The survey results show that the heat-related WPL for the year was 6.6 days for developing countries and 3.5 days for developed countries. The heat-related WPL has significant negative correlation with GDP Per Capita (cc=-0.63), indicating that the WPL is inversely proportional to the level of development. They identified the regions of vulnerability to heat waves that might have been overlooked in the past, especially the regions such as Central Asia and northern Europe due to relatively low adaptability to heat.

They further estimated the WPL for the future in the Representative Concentration Pathways (RCPs) scenarios( greenhouse gas concentration trajectory adopted by the IPCC and aims to represent the different atmospheric concentration change and climate futures). When global warming reaches 1.5, 2, 3 and 4°C respectively, the average WPL will be 9 (19), 12 (31), 22 (61) and 33 (94) days for developed (developing) countries. Countries in Southeast Asia in a 1.5°C-warming world would suffer the same loss as the developed countries would in a 4°C-warming world. This quantitatively addressed the severe situation that developing countries would face under global warming.