Create and use a data clock

A data clock is a circular chart that is divided into cells by a combination of concentric circles and radial lines, similar to the spokes on a bicycle wheel. The concentric circles divide the data in one way, such as by month, and the radial lines divide the data in a different way, such as by day of the month.

Using a data clock, you can visualize the distribution of your data in two dimensions, allowing you to look for patterns that you might otherwise miss. Data clocks are useful for visualizing trends in temporal data to understand how much data exists at different periods of time.

Data clocks can answer questions about your data, such as: What is the temporal distribution of a dataset at two different frequencies?


A crime analyst is studying theft-related crimes in her city. She wants to know which months and days of the week have the most and least incidents so that she can look for patterns and root causes of crime. A data clock can be used to visualize the relative prevalence of crimes throughout the year.

Data clock showing the number of crime incidents for each month and day of the week

Create a data clock

To create a data clock, complete the following steps:

  1. Select one of the following combinations of data:
    • Two string fields String field
    • Two string fields String field plus a number Number field or rate/ratio field Rate/ratio field

    If you do not select a number or rate/ratio field, your data will be aggregated and a count will be displayed.

    You can search for fields using the search bar in the data pane.

  2. Create the data clock using the following steps:
    1. Drag the selected fields to a new card.
    2. Hover over the Chart drop zone.
    3. Drop the selected fields on Data Clock.

You can also create charts using the Chart menu above the data pane or the Visualization type button Visualization type on an existing card. For the Chart menu, only charts that are compatible with your data selection will be enabled. For the Visualization type menu, only compatible visualizations (including maps, charts, or tables) will be displayed.

Data clocks can also be created using View Data Clock, which is accessed from the Action button Action under Find answers > How has it changed?

Usage notes

Data clocks are symbolized using graduated colors.

The Legend button Legend opens the Layer options pane. The Layer options pane contains the following functions:

  • The Legend tab Legend can be used to make selections on the chart. The pop out legend button Pop out legend displays the legend as a separate card on your page.
  • The Options tab Options changes the classification type and number of classes.
  • The Style tab Style changes the color palette and outline color.

Use the Visualization type button Visualization type to switch directly between a data clock and other visualizations, such as a grouped summary table, a line graph with a Subgroup field, or a heat chart.

When you create a data clock, a result dataset Results with the string and number fields used to create the chart will be added to the data pane. The result dataset can be used to find answers with nonspatial analysis using the Action button Action.