Hi Lo graphs display not only a Y-value for each X-value, but a range of Y-values for a given X-Value. Hi Lo graphs are typically used to display error bars or the trading range of a stock and its closing value for each period. The range of Y-values represent the low, standard (closing), and the high values for the given X value.
Just as with line and bar charts, Hi Lo graphs can show multiple sets of data. You can use the Data Sets dialog box to change the horizontal tick marks into boxes, circles, etc. You can also use the Skew Data button in the General graph dialog to offset the data sets from each other. This helps in discriminating the data points of one data set from another. The points in each data set can also be connected with line segments or splines. You have the same flexibility in determining the look of the Hi Lo graph as you do with Line and Scatter graphs.