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.
This Increase icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 6,000 icons, all in the same style and quality.