The graphical desktop meter consists of two sections. The upper green/red 'period' meter, and the lower blue 'usage' progress bar. The lower 'usage' progress bar shows the percent of your monthly plan allocation that you have used so far. The upper green/red 'period' meter shows how far through the plan period (month) you are. As time passes during the month, the boundary between the green and red moves from left to right. If you are using your downloads evenly over the month, the usage bar and the period meter will keep pace with each other. If you are downloading heavily, the usage bar will overtake the period meter and be in the 'red' area. If you are downloading lightly, the usage bar will be behind the period meter and be in the 'green' area.