Just to clarify your question, are you asking what a market share bar graph is?
If so, a market share bar graph is a bar or column chart that shows the representative share of a series of products or companies. Generally, consumer market share data is tracked by a market research company, such as Ipsos, but can also be tracked by trade publications, industry associations, etc. In some cases, you can't get independent market share data and may have to estimate it. There are various different ways to estimate market share, which will depend upon your product and industry. The first is to try and determine the overall market size, which you can try to assess through publicly available data sources, typically available from government websites. From there, depending upon the product or market, you may be able to determine approximate annual spend on a type of product from looking at the capital budgets or expenditures of publicly traded companies, or average household spend on product categories from population or industry statistics. You may also be able to observe product sales and determine the approximate percent of each product sold at a given location.
The bar graph itself will show the relative market share of the tracked products against the entire product category. As a simple example, if the overall annual product category sales volume for widgets is $1M and Widget 1 sold $450K, Widget 2 sold $325K, Widget 3 sold $175K, and Widget 4 sold $50K, you would graph each of these as a percent of total sales:
* Widget 1 = 45%
* Widget 2 = 32.5%
* Widget 3 = 17.5%
* Widget 4 = 5%
Hopefully this helps and answers your question!
The Bar graph of market share of the product total addressable market (TAM) in this example shows book ends, books (hardcover, paperback) etc and % of each. https://www.google.com/search?q=bar+graph+share+marketing&client=safari&rls=en&sxsrf=AOaemvJ-Cfg20DTYuvJyZ0IEKymhdRyxTA:1632865250758&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjT1PKJ0aLzAhVSqZ4KHRS0Bj8Q_AUoAXoECAEQAw&biw=1124&bih=587&dpr=1#imgrc=Zj2UvAzKB6j44M
This is the simplest way to explain it and Doug's answer is very accurate.