Zwyżkowy and other 84,100 icons from Icons8 icon pack follow the visual guidelines of the operating systems: Windows, iOS, Android KitKat, and Material. PNG format is free up to 100x100 px. Icons are availble for download in PNG and vector (SVG, PDF, EPS, and more).
This concerns investing money. When stocks are on the rise it is called bullish. The symbol is an arrow on top of a series of lines in a row standing upward and progressing higher and higher. The arrow follows the highness of the lines.