Go to a dashboard and click on Add gadget.
Search for Multiple Filters Statistic Bar Chart Gadget (Horizontal) and click on Add gadget next to it.

Settings	Description	Default
Title	The title of the gadget
X Axis Label	The x-axis label for the bar chart	Issue Count
Y Axis Label	The y-axis label for the bar chart	Assignee
Statistic Type	Select the statistic type to display
Color Scheme	Select the color scheme for the bar chart Basic Contrasting Shades Warm Custom	Basic
Add Filter	Click to add filter ^{*Up to 12 filters can be added}
Filter n	Select the filter(s) or enter JQL to plot the bar chart.
Alias n	Display name for Filter n
Calculation Mode n	Calculation mode for Filter n
Color n	Bar color for Filter n
Display Type	Select whether to display bar chart, data table or both Bar Chart Only Data Table Only Bar Chart and Data Table	Bar Chart Only
Display Mode	Select whether to group or stack the bars Grouped Stacked	Grouped
Data Labels	Select whether to show/hide data labels in bar chart Show Hide	Show
Display Time In	Select the duration unit for time fields calculation mode (e.g. Time Spent) Hours Days Weeks	Hours
Sum Up Rows	Select whether to sum up rows in data table Yes No	Yes
Tick Interval	Specify the interval between each tick on the x-axis