Linear Gauges are those which are usually used to show a value or an amount once. These gauges do not need a lot of special chart elements such as legend, labels, tooltips, as they have to be understandable and simple. Though, sometimes those elements an be added for some needs, like in this case.
This Chart demonstrates two Linear Gauges with the data about the patient's blood before glucose loading and two hours after. These gauges are a great help for doctors to set the diagnosis and the appropriate treatment. The markers on both gauges point on the impaired glucose tolerance level, and in both cases it becomes higher than the highest value of normal tolerance. The chart has a legend that is not interactive, and both gauges are divided into three ranges representing different glucose tolerance. Both gauges use labels to make the levels of glucose tolerance evident. Tooltips are disabled.