This example visualizes the cumulative total of events from 1949 to 2019, with each year’s running total mapped to a bar in a simple bar chart. The visualization uses D3 v5’s `select` and `csv` functions to load data from a local CSV file, parse the numeric `running_total` column, and then append a fixed-width, fixed-height `rect` for each data point. The code does not scale the bars based on value, so all rectangles appear identical in size.