I thought the dashboard indicated the full usage for the previous day. Then I noticed the numbers changed during the day. I'm trying to track and understand my bandwidth usage. What is the time lag between usage and showing up on the dashboard?
It can vary, usually will update every 15 minutes, but can take up to 24 hours at times. You may wish to install one of the third party data measuring tools, such as NetWorx or BitMeter2. Either of these will give you usage by the hour, updates are very rapid, and they are free. http://www.hongkiat.com/blog/monitor-internet-usage/