Missing info. in Sparkline chart ng-docs

Please add a description of 'total' to the chartData ng-doc 

chartData     object  the data to be shown as an area chart
.xData - Array, X values for the data points, first element must be the name of the data
.yData - Array, Y Values for the data points, first element must be the name of the data
**.total - (optional)  The Total amount, used when determining percentages**
