Approximately 85% of the world's population live in the Eastern Hemisphere.
The line demarcating the eastern and western hemisphere is an arbitrary convention, unlike the equator (an imaginary line running across the middle of the earth), (equidistant from the Earth's poles) which divides the northern and southern hemispheres. The Prime Meridian at 0° longitude and the International Date Line around 180° longitude are the conventionally accepted boundaries, since they divide eastern longitudes from western longitudes. Using this demarcation puts portions of western Europe, Africa, and eastern Russia in the western hemisphere, thereby diluting its usefulness for cartography as well as for geopolitical constructs since all of Eurasia and Africa are typically included in the eastern hemisphere. Consequently, the meridians of 20°W and the diametrically opposed 160°E are often used, which includes all of the European and African mainlands but also includes a small portion of northeast Greenland (typically reckoned as part of North America) and excludes more of eastern Russia and Oceania (e.g., New Zealand).