A coronavirus line chart tracks cumulative global deaths over time, with a horizontal marker line highlighting the 5,000,000-death threshold. The SVG visualization uses React to render a black path generated by d3.line, scaled with d3.scaleTime and d3.scaleLinear. Data comes from the CSSE COVID-19 time series CSV, aggregated daily via d3.csv and timeParse. The marker line is explicitly positioned using the y-scale’s output for 5,000,000, emphasizing the milestone against the full death-total trajectory.