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What Is a Chart?
A chart is a summary of item data presented in a graphical format. When you create a chart, you can restrict what data is included based on the values in standard or custom item fields. For example, you may want to see only the data for items with a Type field value of Defect.
You can create charts using one of four chart types: trend chart, distribution chart, item fields chart, or item fields trend chart.
A trend chart reports item data over a specified period of time summarized at specific intervals. For example, you may want to see the number of defects created over the last month, summarized on a weekly basis. You also have the option of restricting the data to items belonging to a specific project or projects. For example, you may want to see only the number of defects created over the last month for the Cosmos project.
A distribution chart reports item data for items based on an existing query. For example, you may want to base your chart on a query that shows open items for a specific project in order to see the current number of defects for that project. You can then design the chart to break down the current number of defects based on a specified field value. For example, you may want to see the current number of defects broken down by state.
In a distribution chart, you can also perform aggregate operations against numeric fields in items returned by an existing query. Aggregate operations allow you to add numeric field values, calculate the average of multiple numeric field values, retrieve the smallest or largest numeric field value in a group of items, or count the number of items returned by an existing query. For example, in addition to creating a distribution chart that groups several Project items by state, you can also add the Budget field in each state grouping to display a total budget by state. For more information on computed expressions, see “What are Computed Expressions?”.
An item fields chart reports numeric field data from items based on an existing query and a computed expression. The computed expression determines chart values by performing arithmetic calculations between numeric fields in each item returned by the query. For example, you may want to base your chart on a query that shows active Project items and create a computed expression that calculates the discrepancy between the Estimated Cost and Actual Cost fields in each Project item returned by the query.
An item fields trend chart reports numeric field values over a specified period of time summarized at specific intervals. For example, an item fields trend chart could report on the changing values of the Planned Effort field for several Project items over a period of several months.
Charts can be displayed in a number of different graph styles. You can choose from line, bar, pie, XY (scatter), or bubble formats. You can customize the colors, legend, and orientation of the graph, and you can make bar and pie graphs three-dimensional. You can also display chart data in table format.
If you are reporting on a large number of field values, you can use aliases to group the data under a broader category. For example, if you are reporting on all possible states for an item, you could assign an alias of In Work to both the In Progress and In Development field values. You can also use aliases to give a single field value a more meaningful name.