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The site presents information to the user that is not visually cluttered. The user's locus of attention on their main User Page directs them to the most pertinent information: when bills are due and how much the users owe. The timeline scrollbar is always visible, bit it is never intrusive for the user. Additionally, the user's username, the logout option, and the button for user's preferences are always located in the same part of the page header, which makes them easier for the user to find.
Efficiency
Error Prevention
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