An assessment results viewer displays the results of assessments that quantify the performance of an aspect of a computing device. The viewer presents both an overview of the collected data and mechanisms for displaying ever-increasing details, including raw data itself. The viewer further provides actionable information to the user that can offer the user guidance, or otherwise suggest potential courses of action. The viewer automatically aggregates multiple iterations of the same assessment to generate derivative overview data, and automatically aligns data collected by the same assessment across multiple job files. Such aggregation and alignment is performed by reference to metadata, including identifying information. Data can be presented in tabular form, and users can pivot along different axis to focus on groupings of data.