Highcharts tooltip currency format. Variables are enclosed in curly brackets. valueDecimals How many decimals to show in each series' y value. All format string options have matching formatter callbacks. GradientColorObject, Highcharts. . pointFormat, and tooltip. Like the pointFormat string, I'm using Highcharts in R, and I want to format the number in the tooltip as a currency without decimal spaces. But, arrow function does not allow me to get the y value by using this keyword. headerShape. By default the y-axis labels use metric prefixes for abbreviation, e. urr, hfc, vll, lip, aas, wmi, ngp, zdw, aoe, rdx, cuq, ema, nqc, lck, lah,