You can't produce boxplots directly in EXCEL but there is a rather convoluted work around described here. I also reproduce Microsoft's solution below for some example data.
1. In a new worksheet, type the following data:
A1: Statistic |
B1: a |
C1: b |
D1: c |
||
A2: median |
B2: 40 |
C2: 45 |
D2: 50 |
||
A3: q1 |
B3: 20 |
C3: 22 |
D3: 30 |
||
A4: min |
B4: 10 |
C4: 15 |
D4: 18 |
||
A5: max |
B5: 100 |
C5: 110 |
D5: 90 |
||
A6: q3 |
B6: 70 |
C6: 75 |
D6: 57 |
||
2. Select cells A1:D6. On the Insert menu, click Chart.
3. On the Standard types tab, click Stock under Chart type, and then click the fourth chart sub-type.
The following explanation appears below the chart sub-type: Volume-Open-High-Low-Close. Requires five series of values in this order.
4. Click Next.
5. On the Data Range tab, click Rows under Series in, and then click Next.
6. On the Legend tab, click to clear the Show legend check box.
7. On the Axes tab, click to clear the Value (Y) Axis check box under Secondary axis, and then click Finish.
8. Click once on any one of the coloured columns to select the series. Do not click one of the white columns.
9. On the Chart menu, click Chart Type. Under Chart type, click Line, and then click OK.
A line that connects the three white columns appears in the chart.
10. Click once on the line, and then click Selected Data Series on the Format menu and under Display line choose None and under Display marker choose None. Click OK.
After some tidying up including the removal of the gridlines and the changing of the background and box colours you should end up with something like this made using EXCEL 2003.
Lane and Sandor (2009) advocate and illustrate the use of boxplots because they encapsulate graphically information on medians, interquartile ranges, ranges and outliers.
References
Elliott, J and Marsh, C (2008) Exploring Data: An Introduction to Data Analysis for Social Scientists. Second Edition. Polity Press:Cambridge. Chapter 8 introduces boxplots.
Lane, DM and Sandor, A (2009) Designing better graphs by including distributional information and integrating words, numbers and images. Psychological Methods 14(3) 239-257.