Changing a Chart's Size and Position
If you place the chart as an object on an existing worksheet, Excel creates the chart in a default size and position. The chart becomes a worksheet object, and you can change its size as you would that of any other object, by selecting it and dragging handles. You can move it by dragging any part of the chart outside its plot area.
To change a chart's size while keeping its center stationary, hold down Ctrl while you drag. To change a chart's size while maintaining its current aspect ratio, hold down Shift while you drag a corner handle.
When you resize a chart, Excel adjusts the size of all chart text. If you're not happy with the adjustment, you can use formatting commands to increase or decrease the text size. ...