# Bar Graph: Bar Graph Definition and Examples, Types of Bar Charts

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**Bar graphs** are the representation of data (generally grouped), in the form of vertical or horizontal rectangular bars, where the length of bars is proportional to the measure of data. They are also known as bar charts. Bar graphs are one of the means of data handling.

The collection, presentation, analysis, organization and interpretation of observations or data is known as statistics. The statistical data can be represented by various methods like tables, bar graphs, pie charts, histograms, frequency polygons etc.

## Bar Graph Definition

The representation of a group of data, in the form of vertical or horizontal rectangular bars, where the lengths of the bars are equivalent to the measure of data, are known as bar graphs or bar charts.

The bars drawn are of uniform width and the variable quantity is represented on one of the axes. Also, the measure of the variable is depicted on the other axes.

The heights or the lengths of the bars denote the value of the variable and these graphs are also used to compare certain quantities. The frequency distribution tables can be easily represented using bar charts which simplify the calculations and understanding of data.

## Types of Bar Charts

The bar graphs can be vertical or horizontal. The primary feature of any bar graph is its length or height. If the length of the bar graph is more, then the values are greater of any given data.

Bar graphs normally show categorical and numeric variables arranged in class intervals. They consist of an axis and a series of labelled horizontal or vertical bars. The bars represent frequencies of distinctive values of a variable or commonly the distinct values themselves. The number or values on the x-axis of a bar graph or the y-axis of a column graph are called the scale.

The types of bar charts are as follows:

Vertical bar chart

Horizontal bar chart

Range bar chart

### Vertical Bar Graphs

When the group of data are represented vertically in a graph or chart with the help of bars, where the bars denote the measure of data, such graphs are called vertical bar graphs. The data is represented along the y-axis of the graph and the height of the bars shows the values.

### Horizontal Bar Graphs

When the group of data are represented horizontally in a chart with the help of bars, then such graphs are called horizontal bar graphs, where the bars shows the measure of data. The data is depicted here along the x-axis of the graph and the length of the bars denote the values.

## Bar Graph Examples

For the understanding of the type of bar graphs, we take the following examples:

**Example 1: In a firm of 400 employees, the percentage of monthly salary saved by each employee is given in the following table. Represent it through a bar graph.**

Saving (in percentage) | Number of Employees (Frequency) |

20 | 105 |

30 | 199 |

40 | 29 |

50 | 73 |

Total | 400 |

Solution:

Vertical Bar Graph,

Here the number of employees represented along with y- axis. And x β axis represent the Saving in percentage.

Now we also represent this data using a horizontal bar graph.

Here the number of employees represented along with x - axis. And y β axis represent the Saving in percentage

**Example 2: A cosmetic company manufactures 4 different shades of lipstick. The sale for 6 months is shown in the table. Represent it using bar charts.**

Month | Sales (in units) | |||

Shade 1 | Shade 2 | Shade 3 | Shade 4 | |

January | 4500 | 1600 | 4400 | 3245 |

February | 2870 | 5645 | 5675 | 6754 |

March | 3985 | 8900 | 9768 | 7786 |

April | 6855 | 8976 | 9008 | 8965 |

May | 3200 | 5678 | 5643 | 7865 |

June | 3456 | 4555 | 2233 | 6547 |

Solution:

The below graph represents the given data in vertical bar graph.

**Example 3: The variation of temperature in a region during a year is given as follows. Depict it through graph (bar).**

Month | Temperature |

January | |

February | |

March | |

April | |

May | |

June | |

July | |

August | |

September | |

October | |

November | |

December |

Solution: As the temperature in the given table has negative values, it is easier to represent in horizontal than vertical bar graph.

Here below the represent the of the given data.

## Uses of Bar Graphs

Bar graphs are used to match things between different groups changes over time. Yet, when trying to estimate change over time, bar graphs are most suitable when the changes are bigger.

Bar charts possess a discrete domain of divisions and are normally scaled so that all the data can fit on the graph. When there is no regular order of the divisions being matched, bars on the chart may be organized in any order. Bar charts organized from the highest to the lowest number are called Pareto charts.

## Bar Graph Question

**Question: The bar graph below shows the foreign exchange reserves of a country (in million US $) from 1991 - 1992 to 1998 - 1999.**

Q. 1 The foreign exchange reserves in 1997-98 was how many times that in 1994-95?

Solution:

Here above given bar graph of foreign exchange of reserve of a country.

The foreign exchange reserve in 1997-98 is 4320.

The foreign exchange reserve in 1994-95 is 3360.

Here we have to find out the how many times 1997-98 than 1994-95.

So, we find the ratio of these two year,

Required ratio

Q. 2 For which year, the percent increase of foreign exchange reserves over the previous year, is the highest?

Solution:

As shown bar graph,

There is an increase in foreign exchange reserves during the years 1992 - 1993, 1994 - 1995, 1996 - 1997, 1997 - 1998 as compared to previous years.

The percentage increase in reserve during these years compared to previous year are:

For 1992 β 1993,

The previous year 1991 1992 exchange reserve is 2640.

The exchange reserve in 1992 β 1993 is 3720.

Here first we subtract the 2640 from the 3720.

Then, we divided 1080 by 2640.

We multiply the 0.4090 to 100, and we get that,

Same thing using in the other years.

For 1994 -1995

For 1996-1997

For 1997-1998

Here clearly seen that percentage increase over previous year is highest for 1992 -1993.