Adding start and end lines are helpful ways to mark the most recent and least recent data points, as well as giving excellent aesthetic features.
In this I will be showing how to add these start and end dots to simple lines on Tableau desktop, using the classic sample-superstore dataset.
first will do a line graph, I want to show the total sales for each month in each year. I have dragged my order date field to the columns tab and selected MONTH from the dropdown and then dragged my sales field to the rows tab. I also formatted my chart to remove the header so, I just have the bare line graph.
Then I created a calculated field, naming it "Dots. In this calculated field, input the following formula.
IF LAST()=0 OR FIRST()=0 THEN SUM([SALES]) END
This calculation checks if a data point is either the first or last data point using FIRST() and LAST() functions.
3. Drag this new calculated field onto the rows tab.
click on the dots pill and click dual axis in the drop down. Then right-click on the axis on the right-hand side of the chart and select synchronize axis from the menu.
4. Navigate to the dots marks card and change the marks type to circle and use the size feature to size appropriate.
Done! we have added these start and end dots to the line graph.