We can calculate cumulative sum by applying the cumulative formula to a cell, and then repeat the action for subsequent cells. We can use these values to plot a cumulative line graph or chart. This tutorial will teach us how to calculate cumulative sum and plot a cumulative graph.

*Figure 1: Cumulative Sum: Cumulative Chart*

**Data for ****Cumulative Sum in Excel**

- We will tabulate our data according to the period or date of sales.

*Figure 2: Table of Data*

We will calculate the cumulative sales by starting with **Cell D4. **The value of the cumulative sum of the first month would be the same as the first sale, since there has not being subsequent sales. A cumulative sale accumulates over an extended period of time.

*Figure 3: Cumulative sale for January*

- We will now type this formula

into**=SUM(D4+C5)****Cell D5**

*Figure 4a: Cumulative Sum of the Second month*

We will click **OK**

*Figure 4b: Cumulative sum formula for February*

- We will
**double-click**on the**fill handle**(the**small box at the bottom right**of Cell D5 as shown in Figure 4b) and drag down to**Cell D10**to calculate the cumulative sum for the remaining months**(March – July)**

*Figure 5: Cumulative sum of the remaining months*

**Cumulative chart**

- We will highlight the data in the
**Month**and**Sales**columns and prepare a**chart**with them by clicking the**insert**icon. We will click**recommended chart**from the**chart group**and select the first chart.

*Figure 6: Cumulative Chart*

**To add the cumulative sales, we will right-click on the chart and click on select data. We will now click on add to open the Edit Series dialog box. We will click on Series name and click on Cell D3 to input the Series name as “cumulative sales”. We will thereafter, click on Series values and highlight the data from Cells D4 to D10, then we will click on OK, and again, OK**

*Figure 7a: Inputting the cumulative sales’ title and data*

*Figure 7b: Inputting the cumulative sales’ title and data*

- We will
**right-click**any of the**cumulative sum bars**and select**format data series**, then we will select**secondary axis**

*Figure 8: Changing to Secondary Axis*

**We will now change the chart type to line by clicking on design and select change chart type**

*Figure 9a- Change chart type*

**We will scroll to where the cumulative sales is displayed and click on the drop-down arrow to change it to line. Thereafter, we will click OK**

*Figure 9b: Change Chart type to line*

- We will now right-click on the line to
**add data label**

*Figure 10: Cumulative line chart*