Histogram in Excel!

Histogram of arrivals per minute.svg(From Wikipedia) In statistics, a histogram is a graphical representation of the distribution of data. It is an estimate of the probability distribution of a continuous variable and was first introduced by Karl Pearson. A histogram is a representation of tabulated frequencies, shown as adjacent rectangles, erected over discrete intervals (bins), with an area proportional to the frequency of the observations in the interval. The height of a rectangle is also equal to the frequency density of the interval, i.e., the frequency divided by the width of the interval. The total area of the histogram is equal to the number of data. A histogram may also be normalized displaying relative frequencies. It then shows the proportion of cases that fall into each of several categories, with the total area equaling 1. The categories are usually specified as consecutive, non-overlapping intervals of a variable. The categories (intervals) must be adjacent, and often are chosen to be of the same size. The rectangles of a histogram are drawn so that they touch each other to indicate that the original variable is continuous.

This example teaches you how to create a histogram in Excel.

1. First, enter the bin numbers (upper levels) in the range C3:C7.
Bin Numbers
2. On the Data tab, click Data Analysis.
Click Data Analysis
Note: can't find the Data Analysis button? Click here to load the Analysis ToolPak add-in.
3. Select Histogram and click OK.
Select Histogram
4. Select the range A2:A19.
5. Click in the Bin Range box and select the range C3:C7.
6. Click the Output Range option button, click in the Output Range box and select cell F3.
7. Check Chart Output.
Histogram Parameters
8. Click OK.
Histogram First Result
9. Click the legend on the right side and press Delete.
10. Properly label your bins.
11. To remove the space between the bars, right click a bar, select Format Data Series and change the Gap Width to 0%. Select Border Color to add a border.
Histogram Final Result 

 Source: http://www.excel-easy.com/examples/histogram.html