data visualization: basics
Area charts on steroids
Area charts are being used to create some of the most interesting visualizations on the Web. Using some simple math will allow us to create something similar to a New York Times visualization about how people spend their day.
This graphic takes the area chart a step further by converting the totals to a percentage of the whole. You can do this in Google docs with some simple math. Don't worry, the spreadsheet is going to do all the work.
1. Move the existing gadget out of the way and add the label "Total" in cell F1. In cell F2, type "=SUM(B2:D2)" and hit Enter. This function adds all the cells in the range (B2:D2).
2. Once the total appears, click on cell F2. Notice the box that outlines the cell has a small box in the bottom right corner.
3. Click on that box and drag down to cell F13. This adds the SUM equation to each row and adjusts the range. You now have a new total of each row.
Build a second grid
1. Select (shift click) cell A1 through cell A13. Copy and then click on cell A21 and paste.
2. Create new column labels: Type "Full time" in cell B21; Type "Part time" in cell C21; Type "Unemployed" in cell D21.
3. Now we need to calculate the percentage for cell B22. That equation looks like this: "Full time employment" divided by "Total" X 100. So in cell B22, type "=B2/F2*100" and hit enter.
4. You now have all the percentages calculated for Full time employment.Once that's done, select cell B22, click on the square in the lower-right corner and drag down to cellB33.. Repeat in cell C22 using the formula =C2/F2*100. Repeat in cell D22 using the formula =D2/F2*100
5. Time to clean up the data. Let's get rid of all those decimals. Shift-select cells B22 through D33. Click on the 123 button to get a drop down menu and select the second option "1,000." This will round the percentages.
6. Move your gadget back the the center of your spreadsheet. Edit the gadget by changing the range in to A21:D33 and click "Apply and close." The chart now shows how the percentage change over time.
While this doesn't have all the functionality of the New York Times graphic, you can still visualize a large dataset and build an intricate, interactive graphic.