The <dotj:grid> tag supports a rudimentary reporting feature that we call the Control-Break feature. Often,
values are repeated down a column, and it is common to supress the subsequent values. This effect can be achieved by setting
the breaktype attribute to simple.
In this spirit, we've also added support for subtotals as well as running totals. Try each of these below to see what effect
they have on the grid. Note that the breaktype attribute is on the <dotj:columns> tag. In addition, you
must set the controlbreak attribute to true on the column(s) that you wish to control break on.