Graphing is one of the most effective ways to display datasets, financial scenarios, and statistical functions in a way that can be understood easily by the users. When you give an individual a list of 40 different numbers and ask him or her to draw a conclusion, it is not only difficult, it may be impossible without the use of extra functions. However, if you provide the same individual a graph of the numbers, they will most likely be able to notice trending, dataset size, frequency, and so on. Despite the effectiveness of graphing and visual modeling, financial and statistical graphing is often overlooked in Excel 2010 due to difficulty, or lack of native functions.
In this article, you will learn to not only add reusable methods to automate graph production, but also how to create graphs and graphing sets that are not native to Excel. You will learn to use box and whisker plots, histograms to demonstrate frequency, stem and leaf plots, and other methods to graph financial ratios and scenarios.
Charting financial frequency trending with a histogram
Frequency calculations are used throughout financial analysis, statistics, and other mathematical representations to determine how often an event has occurred. Determining the frequency of financial events in a transaction list can assist in determining the popularity of an item or product, the future likelihood of an event to reoccur, or frequency of profitability of an organization. Excel, however, does not create histograms by default.
In this recipe, you will learn how to use several functions including bar charts and FREQUENCY functions to create a histogram frequency chart within Excel to determine profitability of an entity.
When plotting histogram frequency, we are using frequency and charting to determine the continued likelihood of an event from past data visually. Past data can be flexible in terms of what we are trying to determine; in this instance, we will use the daily net profit (Sale income Versus Gross expenses) for a retail store. The daily net profit numbers for one month are as follows:
$150, $237, -$94.75, $1,231, $876, $455, $349, -$173, -$34, -$234, $110, $83, -$97,
-$129, $34, $456, $1010, $878, $211, -$34, -$142, -$87, $312
How to do it…
Utilizing the profit numbers from above, we will begin by adding the data to the Excel worksheet:
- Within Excel, enter the daily net profit numbers into column A starting on row 2 until all the data has been entered:
We must now create the boundaries to be used within the histogram. The boundary numbers will be the highest and the lowest number thresholds that will be included within the graph. The boundaries to be used in this instance will be of $1500, and -$1500.
These boundaries will encompass our entire dataset, and it will allow padding on the higher and lower ends of the data to allow for variation when plotting larger datasets encompassing multiple months or years worth of profit.
We must now create bins that we will chart against the frequency. The bins will be the individual data-points that we want to determine the frequency against. For instance, one bin will be $1500, and we will want to know how often the net profit of the retail location falls within the range of $1500. The smaller the bins chosen, the larger the chart area.
You will want to choose a bin size that will accurately reflect the frequency of your dataset without creating a large blank space. Bin size will change depending on the range of data to be graphed.
- Enter the chosen bin number into the worksheet in Column C. The bins will be a $150 difference from the previous bin.The bin sizes needed to include an appropriate range in order to illustrate the expanse of the dataset completely. In order to encompass all appropriate bin sizes, it is necessary to begin with the largest negative number, and increment to the largest positive number:
The last component for creating the frequency histogram actually determines the frequency of net profit to the designated bins. For this, we will use the Excel function FREQUENCY.
- Select rows D2 through D22, and enter the following formula:
- After entering the formula, press Shift + Ctrl + Enter to finalize the formula as an array formula.Excel has now displayed the frequency of the net profit for each of the designated bins:
The information for the histogram is now ready. We will now be able to create the actual histogram graph.
- Select rows C2 through D22.
- With the rows selected, using the Excel ribbon, choose Insert | Column:
- From the Column drop-down, choose the Clustered Column chart option:
Excel will now attempt to determine the plot area, and will present you with a bar chart. The chart that Excel creates does not accurately display the plot areas, due to Excel being unable to determine the correct data range:
- Select the chart. From the Ribbon, choose Select Data:
From the select Data Source window that has appeared, you will change the Horizontal Axis to include the Bins column (column C), and the Legend Series to include the Frequency (column D).
- Excel will also create two series entries within the Legend Series panel; remove Series2 and select OK:
Excel now presents the histogram graph of net profit frequency:
- Using the Format graph options on the Excel Ribbon, reduce the bar spacing and adjust the horizontal label to reduce the chart area to your specifications:
Using the histogram for financial analysis, we can now determine that the major trend of the retail location quickly and easily, which maintains a net profit within $0 – $150, while maintaining a positive net profit throughout the month.
How it works…
While a histogram graph/chart is not native to Excel, we were able to use a bar/column chart to plot the frequency of net profit within specific bin ranges.
The FREQUENCY function of Excel follows the following format:
=FREQUENCY(Data Range to plot, Bins to plot within)
It is important to note that within the data range, we chose the range A:A. This range includes all of the data within the A column. If arbitrary or unnecessary data unrelated to the histogram were added into column A, this range would include them. Do not allow unnecessary data to be added to column A, or use a limited range such as A1:A5 if your data was only included in the first five cells of column A.
We entered the formula by pressing Shift + Ctrl + Enter in order to submit the formula as an array formula. This allows Excel to calculate individual information within a large array of data.
The graph modifications allowed the bins to show frequency in the vertical axis, or indicate how many times a specific number range was achieved. The horizontal axis displayed the actual bins.
The amount of data for this histogram was limited; however, its usefulness was already evident. When this same charting recipe is used to chart a large dataset (for example, multiple year data), the histogram becomes even more useful in displaying trends.