How to Construct a Stem-and-Leaf Plot

An easy way of presenting data in an easy-to-read and organized style is by constructing a stem-and-leaf plot. It only takes a few simple steps to make and the distribution can be referred to and read with a glance of the eye.

Instructions

1. List the data in reference from least to greatest on a scrap sheet of paper.

2. Identify the least and greatest common place value. For instance, if your numbers are 26, 37, 23, 35, 45, 34 and 49, your greatest common place value is the tens place and the least common place value is the ones place.

3. Create the stem. Draw a vertical line long enough to fit three rows of numbers, in this case. The three rows will be for the 20's, the 30's and the 40's listed on your scrap sheet.

4. Fill in the tens place digits on the left side of the vertical line. You should now have a vertical line and to the left of it should read (from top to bottom) 2, 3, 4.

5. Create the leaves. Fill in the ones place digits to the right of the vertical line, but in the corresponding row. The first row should now read as a vertical line with 2 to the left and 3, 6 to the right. This indicates the numbers 23 and 26. The next row should read 3, vertical line, 4, 5, 7, which indicates the numbers 34, 35 and 37. The third row should read 4, vertical line, 5, 9. This represents the numbers 45 and 49. Note that you should not include commas between the numbers when drawing an actual stem-and-leaf plot.

6. List repeat numbers side-by-side. For instance, if the number 10 appears twice in your data, the first row would read 1, vertical line, 0, 0 (followed by any other numbers in the 10's range).

7. Write, for example, the number 25 as 2 5, and draw a single vertical line in between the numbers when taking the data from a stem-and-leaf plot. In other words, you wouldn't write out "vertical line," instead you would draw a small vertical line.

Tips & Warnings

• Negative numbers go at the top of the plot, in ascending order.

• Non-integers must be rounded.

• This plot should only be utilized for small-medium amounts of data plots (approximately 15 to 150).