The size of each space in the above periodic table represents (more or less) the relative abundance of that element on our planet. The serious problem you might not immediately see from the chart is that certain rare elements are also very important, such as helium (He). Helium is crucial in medical technology and aerospace engineering, among other scientific fields, and yet every grocery store in the country has a few balloons filled with the precious gas. If current trends continue, we will have no more usable helium on earth in about forty years. A tip of the hat to Maxime Duprez.