Use a line chart for change over time
50%
When the horizontal axis is time, a line chart is nearly always right. The line itself carries the information, the slope between two points is the rate of change, which is usually the actual question.
Columns can show the same numbers, but at eight or ten points they turn into a wall of bars and the trend stops being visible. The data has not changed; the readability has.
Use the Chart panel to build a line chart of the monthly visitor figures in A1:B9.
The grid for this exercise is part of the paid half.
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