Should the title of the bar graph be small or big

Bar graph titles include the name of the graph, the title of the vertical axes, and the title of the horizontal axes. It is important to title bar graphs carefully so the information makes sense and the graph is easy to read and understand. The general title of the bar graph should provide an overview of the information it contains and give the readers an indication of the data they will be looking at.
So its depend upon the given information to title the graph small or big.

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