This line chart visualizes total opioid overdose deaths in the United States from 1999 to 2019, using data from the CORGIS dataset. Red circles mark each year’s value, and hovering over a dot reveals the exact death count via a tooltip. The chart uses d3.csv to load the data, d3.scaleLinear for both axes, and d3.axisBottom and d3.axisLeft to render ticks. The line and dots are drawn as SVG elements using d3.line and appended circles, with a title appended to each circle for the hover effect.