Placing your chart in the appropriate layout part
Data in charts created in Layout mode is evaluated based on the layout part in which the chart is located.
When you use a calculation to specify a chart title, the title is calculated based on the chart’s layout part.
Note  You cannot place a chart in a portal.
When data is based on the current found set
When Summarized groups of records is selected, FileMaker Pro charts data in
Charts placed in a subsummary layout part use data in the sorted group to create the chart. When there is no sort order, FileMaker Pro charts individual data values in the entire found set. Subsummaries are considered inner summaries, because they display aggregate data from a group within the data set based on the sort order you specify.
Charts placed in a grand summary layout part use data in the outer-most level of each sorted subsummary group to create the chart. Grand summaries are considered outer summaries, because they display an overall summary of aggregated data based on the entire found set. You can also use grand summary layout parts to summarize each subsummary group.
For grand summaries calculated on the current found set, FileMaker Pro assumes you want to chart data in each subsummary group. Therefore, FileMaker Pro expects your x-axis definition (category labels in pie charts) to be the sort field and your y-axis definition (slice data in pie charts) to be a summary field. For example, to create a bar chart that compares the total number of companies per country, you must sort data by country (x-axis or category labels) and summarize data in the Company field (y-axis or slice data) to calculate the number of companies in each country. FileMaker Pro then charts the summarized values by country.
When data is based on the current record (delimited values)
When data is based on related records
Note  If you place a chart in a grand summary part without sorting records, FileMaker Pro will chart data from the entire found set as though the chart had been placed in a header, footer, or body layout part.
How layout parts affect calculated titles in charts
Related topics 
About layout part types
Working with layout parts
Adding a layout part
Changing a layout part