This visualization displays Taiwan’s national and six-municipality demographic trends from 2010 to 2021, comparing natural increase rates against birth, death, marriage, and divorce rates. A dropdown menu lets viewers switch between regions, updating a multi-line chart rendered as SVG. The chart uses d3.scaleLinear and d3.line to draw trends, with axes generated via d3.axisLeft, d3.axisRight, and d3.axisBottom. Data is loaded from a CSV file using d3.csv, and rates are computed by scaling raw counts against population figures.