This is the Wykres warstwowy icon for Windows 10. Here we go. Optimized for 32x32 px, these are the simplest icons in the line style. Downloadable formats are PNG and SVG, among others. Icons8 icon pack is unique in providing a huge number of icons designed by the same team of four designers who create the new icons every working day in the same style and with the same quality. Same cool as the Bat Face, huh.
The area chart has a flat bottom with two sets of line going up and down. The top set of lines has dots interspersed throughout to indicate that it measures something different than the bottom set of lines.