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Glossary of Chart Types
There are many ways to visualize data. This glossary provides an overview of some common
chart types you may encounter in historical documents. Each chart entry includes a basic definition, a description of what kind of information or argument the chart is commonly used to
display, and one or more visual examples from FRASER® (the Federal Reserve Bank of St. Louis
digital library of economic history).
Bolded terms indicate terms defined in this glossary.
Sources of the Example charts begin on page 14.
Some chart types are not included because of their scarcity in the FRASER collection. If you
would like to suggest a chart you think would enhance this glossary, please contact
eva.k.johnston@stls.frb.org and we will consider adding it.

Area chart: A variation of a line chart in which the space underneath the line(s) has been filled in
or shaded (Examples 1 and 2).
Area charts are usually used to compare multiple values that add up to a total (see Example 2),
but they can also be used to emphasize the volume of a given measurement (see Example 1).

Example 1: Area Chart

© 2017, Federal Reserve Bank of St. Louis. Permission is granted to reprint or photocopy this lesson in its entirety for educational purposes,
provided the user credits the Federal Reserve Bank of St. Louis, www.stlouisfed.org/education.

Glossary of Chart Types

Example 2: Area Chart, Multiple Values

Bar chart: A chart using vertical or horizontal bars proportional to the values they represent (Examples 3 to 6). The direction of the bars may or may not be meaningful (see Example 6). Also
known as a bar graph.
Bar charts are useful for showing comparisons of similar or related data. A bar chart with two
or more datasets (see Example 3) can easily show changes within one dataset and differences
between datasets.

Example 3: Bar Chart

Example 4: Stacked Bar Chart

Glossary of Chart Types

Example 5: Bar Chart, Histogram

Example 6: Bar Chart

A stacked bar chart (see Example 4) shows changes in the composition of subgroups or component measurements within a given measurement. It is better at showing changes within a dataset
rather than across datasets.
A histogram is a bar chart that shows the distribution of values over ranges (such as 0-5, 5-10,
and 10-20; see Example 5).
Box plot: A graph that uses a box and lines to show the distribution of data: The box indicates
the first through third quartiles. The lines that extend on either side of the box, often called
“whiskers,” indicate the maximum and minimum values of the data (Example 7). Sometimes a
line is included in the box that indicates the median. Also known as a box-and-whisker plot or
a box-and-whisker diagram.

Glossary of Chart Types

Example 7: Box Plot

Example 8: Box Plot, Min-Max-Average

A type of box plot that depicts only the median and range (Example 8) is called a min-maxaverage chart.
Box plots are useful for showing the central trend of a dataset with numerous observations. A
max-min-average chart shows where the median of the dataset falls in relation to the distribution. In both types, the location of the median along the data line can show whether the data
points are more concentrated in one area of the distribution.

Glossary of Chart Types

Example 9: Bubble Map

Bubble map: A type of cartogram (a map that shows statistical information) that shows the measurement of a given variable as proportionally sized “bubbles” in geographic regions (Example 9).
Bubble maps can quickly show variation of data across states, regions, or countries and allow
for easy comparison between any two areas on the map. Unlike a choropleth map, a bubble
map uses bubble size instead of color to indicate values.
Choropleth map: A map that shows variations in data across a spectrum by using different colors
or, more commonly, different hues of the same color (Example 10). This kind of map visually
represents values of data in geographic regions or subregions such as states or counties.
A choropleth map can easily show ranges of values across and inside geographical boundaries.
Usually a darker or more intense color indicates a higher value.
Diagram: See infographic.
Dot plot: A graph that plots each value of a variable as a single dot and that groups values together
(Example 11).
Dot plots are used to show clusters and outliers in datasets and are clearest when used for
datasets with few data points. A dataset with a larger number of data points might be more
clearly represented with a box plot.

Glossary of Chart Types
Example 10: Choropleth Map: The Range, and,
within the Range, the Degree of Cultivation of
Certain Principal Crops (1870)
NOTE: The following notes appear on the original map:
Explanation of Scales: The no. of bushels, bales or pounds
produced in each county is divided: 1st by the No. of
inhabitants, 2d by the no. of Acres of improved land.
The two quotients are multiplied together, and the square
root of the product is taken as the measure of the importance of the crop to the county and of the county to the
crop of the country. The counties are then grouped by
natural gradation from lowest to highest (No. 1 upwards).
Note: The Shaded Lines in Black indicate the outside limit
of a population of 2 or more to the square mile. The shading points towards the regions which have a population
of less than 2 to the square mile.”
In a few instances, lines in green are run around on the
space covered by the other color, showing the cultivation
of both crops in the same field.

Example 11: Dot Plot
NOTE: In this example, each data point is one dot and each vertical group of dots is one time period.

Glossary of Chart Types
Hub-and-spoke chart: A data visualization used to represent people or things (the hubs) and the
connections between them (the lines, or “spokes”; Example 12).
A hub and spoke chart is more often used for qualitative (descriptive) data rather than quantitative (statistical or numerical) data. Connecting spokes and hub nodes (the point where they
intersect) may be color-coded or standardized by size or shape or individually labeled. These
charts are helpful for showing complex interrelationships.

Example 12: Hub-and-Spoke Chart

Infographic: A visual representation of a process, situation, structure, or explanation intended to
convey information quickly and clearly. Also known as a diagram (Examples 13 to 15).
An infographic mixes text and images to represent information more clearly than a text-only
description or a graphical representation of data alone. Infographics are useful for showing
flows of information, materials, or people or for illustrating steps in a process. An infographic
might be based on a map (see Example 13) or graph, combine multiple charts into one overall
visual story (see example 14), or use a specific shape (see Example 15) to convey information.

Glossary of Chart Types

Example 13: Infographic,
Map-Based

Example 14: Infographic, Timeline

Example 15: Infographic, Shape-Based

Glossary of Chart Types
Line chart: A graph with the individual data points of a data series connected by line segments
(Examples 16 to 18). Also known as a line graph.
A line chart is one of the most common types of charts and is used most often to show a given
measurement at different points in time. One chart may have multiple lines, representing two
or more related measurements, such as the same time in different years (see Example 16) or
different datasets connected by subject matter (see Example 17).
A line chart is useful for showing trends. Line charts with many lines (see Example 18) may be
useful for comparing datasets but can quickly become unclear as they become visually complex.

Example 16: Line Chart, Multiple Years

Example 17: Line Chart, Similar Subject Matter

Example 18: Line Chart, Multiple Lines

Glossary of Chart Types
Map: A graphical depiction of a geographic area, with or without additional information added
(Examples 19 to 21). A map with statistical information is called a cartogram; two specific types
are bubble maps and choropleth maps. A city map is sometimes called a plan.
Maps often make or reinforce arguments subtly by labeling or not labeling certain features (such
as cities or waterways).

Example 19: Map, Country

Example 21: Map, City Blocks
NOTE: The following information appears at the bottom of the
original map: The figures in each block of this section of a map of
Richmond are factors revealing the housing conditions in that block.
Listed from top to bottom in each block are (1) average rental of
the dwelling units; (2) total number of residential structures; (3) percentage of total number of residential structures less than 15 years
old; (4) percentage of total number of dwelling units that are
owner-occupied; (5) percentage of total number of residential
structures that need major repairs; (6) percentage of total number
of structures used for commercial purposes; (7) percentage of total
number of dwelling units that have no private bath; (8) percentage
of total number of residents that are nonwhite.
The basic figures for each block are derived from the real property
survey for the city. Such a map shows the general pattern of neighborhoods, and helps the mortgage lender to recognize and interpret trends which may change the character of neighborhoods.
Dwelling units that are similar in rental, in age, in condition, or
similar with respect to other indicators of quality of housing, tend
to be concentrated in certain areas. Note how few of the structures
in the lowest rental blocks are in good condition, or are owneroccupied. In the better-grade areas, structures are newer, there
are more owner-occupants, and dwellings are generally in good
condition.
Example 20: Map, Regional

Glossary of Chart Types

Example 22: Mixed-Type Chart

Mixed-type chart: A chart that uses more than one type of chart, particularly to show a correlation
between multiple sets of data (Example 22).
These charts can be difficult to read and often rely more heavily on the accompanying text to
explain the argument being made.
Pie chart: A circular chart divided into segments, each of which is proportional to the value it represents (Examples 23 to 25). Pie charts may have additional color or shading of the various “slices”
Pie charts are often used to represent the composition of a whole. Although it is common to
use pie charts to demonstrate the comparative size of various component values, pie charts can
be difficult to read accurately when there are more than a handful of slices of the pie (see Example 24).
An exploding pie chart (see Example 25) further visualizes one or more slices of the chart (e.g.,
by using another pie chart, a bar chart, or some other kind of chart). A polar area diagram
(see Example 26), a kind of pie chart (more popular in the nineteenth century), divides the circle
equally and uses the distance of each section from the center of the circle to indicate the section’s
value (not to be confused with a polar chart, not pictured).

Glossary of Chart Types

Example 24: Pie Chart, Many Slices
Example 23: Pie Chart, Few Slices

Example 25: Exploding Pie Chart

Example 26: Pie Chart, Polar Area Diagram

Glossary of Chart Types
Scatterplot: A graph that plots two variables
as a single dot on the graph. The location
of each dot shows the value for both variables for a single person, place, or thing
(Example 27).
The pattern of the scatterplot shows any
correlation between two measurements.
Most scatterplots also have a line (sometimes known as a “line of best fit”) showing the trend of the correlation.
Table: Data presented in rows and columns.
A table is one of the most common kinds
of charts and is useful for showing many
values at once. Data presented in a table
are called tabular data. Organizing data in
a table is often a precursor to adapting it
into a graph.

Example 27: Scatterplot

Example 28: Table

Glossary of Chart Types

Sources
Example 1: Area Chart: Westcott, Diane N. and U.S. Bureau of Labor Statistics. “Profile of the Teenage Worker.” Bulletin of the United
States Bureau of Labor Statistics, 1980, No. 2039, p. 10; https://fraser.stlouisfed.org/title/4827?start_page=20
Example 2: Area Chart, Multiple Values: Link, Irene. “Relief and Rehabilitation in the Drought Area.” Works Progress Administration
Research Bulletin, June 1937, p. 10; https://fraser.stlouisfed.org/title/839?start_page=17.
Example 3: Bar Chart: U.S. Bureau of Labor Statistics. “Women at Work: A Chartbook.” Bulletin of the United States Bureau of Labor
Statistics, April 1983, No. 2168, p. 13; https://fraser.stlouisfed.org/title/290?start_page=21.
Example 4: Stacked Bar Chart: U.S. Bureau of Labor Statistics. “Employment and Economic Status of Older Men and Women.” Bulletin of the United States Bureau of Labor Statistics, 1952, No. 1092, p. 39; https://fraser.stlouisfed.org/title/4437?start_page=47.
Example 5: Bar Chart, Histogram: Personick, Martin E. “Profiles of Occupational Pay: A Chartbook.” Bulletin of the United States
Bureau of Labor Statistics, 1979, No. 2037, p. 17; https://fraser.stlouisfed.org/title/4828?start_page=25.
Example 6: Bar Chart: Romero, Jessie. “American Made: The Manufacturing Sector Is Stronger Than You Might Think—But New
Vulnerabilities Are Emerging.” Federal Reserve Bank of Richmond Econ Focus, Fourth Quarter 2011, p. 14;
https://fraser.stlouisfed.org/title/3941/item/476954?start_page=16.
Example 7: Box Plot: Federal Open Market Committee. “Summary of Economic Projections” (pg. 2) in “Minutes of the Federal Open
Market Committee.” January 24-25, 2012, p. 18;
https://fraser.stlouisfed.org/title/677/item/23306/content/pdf/20120125statement?start_page=18.
Example 8: Box Plot: Min-Max-Average: Personick, Martin E. “Profiles of Occupational Pay: A Chartbook.” Bulletin of the United States
Bureau of Labor Statistics, No. 2037, p. 11; https://fraser.stlouisfed.org/title/4828?start_page=19.
Example 9: Bubble Map: U.S. Reserve Bank Organization Committee. “St. Louis Sales of Drugs, Patent Medicines & Perfumes.” 1914.
Held in Records of the Federal Reserve System, 1878-1996, Record Group 82 #92, St. Louis, Box 2653, Folder 5;
https://fraser.stlouisfed.org/archival/1344/item/469353?start_page=6.
Example 10: Choropleth Maps: Walker, Francis A. Statistical Atlas of the United States Based on the Results of the Ninth Census 1870.
U.S. Bureau of the Census, 1874, Plate XXXVI; https://fraser.stlouisfed.org/title/64/item/574137?start_page=9.
Example 11: Dot Plot: Federal Open Market Committee. “Summary of Economic Projections” (p. 4) in “Meeting of the Federal Reserve
Open Market Committee.” January 24-25, 2012, p. 20;
https://fraser.stlouisfed.org/title/677/item/23306/content/pdf/fomcminutes20120125?start_page=20.
Example 12: Hub-and-Spoke Chart: U.S. Congress, House Committee on Banking and Currency. “Exhibit 243: Diagram Showing
Affiliations of J.P. Morgan & Co., National City Bank, First National Bank, Guaranty Trust Co. and Bankers Trust Co. of New York City
with Large Corporations of the United States.” February 25, 1913; https://fraser.stlouisfed.org/title/80/item/23678.
Example 13: Infographic, Map-Based: Federal Reserve Bank of San Francisco. “Review of Business Conditions—Twelfth District.”
Economic Review, September 1944, p. 40; https://fraser.stlouisfed.org/title/869/item/33681?start_page=2.
Example 14: Infographic, Timeline: Hostetler, L. Merle. “1890,” in 75 Yrs. of American Finance: A Graphic Presentation, 1861 to
1935. Cleveland Trust Company, 1936; https://fraser.stlouisfed.org/title/162/item/5373?start_page=35 or
https://fraser.stlouisfed.org/75years/presentation.php (scrolling presentation).
Example 15: Infographic, Shape-Based: U.S. Congress, Senate Committee on Banking, Housing, and Urban Affairs. “Petroleum
Product Shortages.” Hearings before the Committee on Banking, Housing, and Urban Affairs, May 7-11, 1973. GPO, 1973, p. 495;
https://fraser.stlouisfed.org/title/214?start_page=499.
Example 16: Line Chart, Multiple Years: Strong, Benjamin. “Gold Reserves, Federal Reserve Bank of New York [1926-1927].” N.d.
Held in Papers of Benjamin Strong, Correspondence with the Federal Reserve Bank of New York: Other Directors of the Federal
Reserve Bank of New York, 1913-1928, Federal Reserve Bank of New York;
https://fraser.stlouisfed.org/archival/1160/item/2259?start_page=31.
Example 17: Line Chart, Similar Subject Matter: U.S. Department of Labor and Bureau of Labor Statistics. Employment and Payrolls.
February 1937, p. 17; https://fraser.stlouisfed.org/title/152/item/5282?start_page=20.
Example 18: Line Chart, Multiple Lines: Andrew, A. Piatt. “Discount Rates in Berlin, London, Paris and New York 1888-1908” in
Financial Diagrams. Volume XXIII. National Monetary Commission, 1911, Plate No. 9;
https://fraser.stlouisfed.org/title/625/item/21503?start_page=15.
Example 19: Map, Country: St. Louis Republic. “Map Showing Division of the United States into Twelve Federal Reserve Districts.”
April 3, 1914, p. 6; https://fraser.stlouisfed.org/timeline/st-louis-fed-centennial#!3.

Glossary of Chart Types
Example 20: Map, Region: U.S. Reserve Bank Organization Committee. “Cincinnati—An Ideal Distributing Center.” 1914. Held in
Records of the Federal Reserve System, 1878-1996, Record Group 82, #4 Vol. 1 Cincinnati , Box 2645, Folder 1;
https://fraser.stlouisfed.org/archival/1344/item/469146?start_page=108.
Example 21: Map, City Block: Federal Home Loan Bank System. “Residential Neighborhoods: Their Growth and Structure.” Federal
Home Loan Bank Review, May 1940, 6(8), p. 251; https://fraser.stlouisfed.org/title/116/item/2104?start_page=4.
Example 22: Mixed-Type Chart: Bush, George H.W. and Council of Economic Advisers. “Economic Report of the President.” February
2004, p. 261; https://fraser.stlouisfed.org/title/45/item/8103?start_page=266.
Example 23: Pie Chart, Few Slices: U.S. Department of Labor Women’s Bureau. “Working Mothers and the Need for Child Care
Services.” May 1967, p. 23; https://fraser.stlouisfed.org/title/249?start_page=24.
Example 24: Pie Chart, Many Slices: U.S. Bureau of the Census. “Cotton” in Statistical Atlas of the United States, July 1914, Plate 468;
https://fraser.stlouisfed.org/title/74/item/492438?start_page=14.
Example 25: Exploding Pie Chart: U.S. Office of Management and Budget. A Citizen’s Guide to the Federal Budget: Budget of the
United States Government, Fiscal Year 1998. February 6, 1997, p. 2; https://fraser.stlouisfed.org/title/424/item/7266?start_page=6.
Example 26: Pie Chart, Polar Area Diagram: Andrew, A. Piatt. “New York Clearing House Banks, Monthly Movements of Cash to
and from Interior” in Financial Diagrams. National Monetary Commission, 1911, Plate No. 19;
https://fraser.stlouisfed.org/title/625/item/21503?start_page=25.
Example 27: Scatter Plot: Federal Reserve Bank of Cleveland. “Government Spending and Employment in Recoveries.” Economic Trends,
April 2013 Supplement, p. 7; https://fraser.stlouisfed.org/title/3952/item/529710?start_page=7.
Example 28: Table: Britain Health of Munitions Workers Committee and U.S. Bureau of Labor Statistics. “Employment of Women and
Juveniles in Great Britain During the War: Reprints of the Memoranda of the British Health of Munition Workers Committee.” Bulletin
of the United States Bureau of Labor Statistics, No. 223, April 1917, p. 17; https://fraser.stlouisfed.org/title/3860?start_page=17.