1. Create a barChart using d3

<!DOCTYPE html>
<meta charset="utf-8">
<style> /* set the CSS */

.bar { fill: pink; }

</style>
<body>

<script src="https://d3js.org/d3.v4.min.js"></script>
<script>

// set the dimensions and margins of the graph
var margin = {top: 20, right: 20, bottom: 50, left: 50},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

// set the ranges
var x = d3.scaleBand()
          .range([0, width])
          .padding(0.1);
var y = d3.scaleLinear()
          .range([height, 0]);

// append the svg object to the body of the page
// append a 'group' element to 'svg'
// moves the 'group' element to the top left margin
var svg = d3.select("body").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
  .append("g")
    .attr("transform",
          "translate(" + margin.left + "," + margin.top + ")");

// get the billionaires data
d3.csv("billionaires.csv", function(error, data) {
  if (error) throw error;
  // console.log(data);

data.forEach(function(d) {
    d.year = d.year;
    d['worth in billions'] = +d['worth in billions'];
   });
  // for aggregating worth in billions
  var nested_data = d3.nest()
    .key(function(d) { return d.year; })
    .rollup(function(worth) { return { "sumworth": d3.sum(worth, function(d) {return parseFloat(+d['worth in billions']);})} })
    .entries(data);
    console.log("nested_data:");
    console.log(nested_data);
  // Scale the range of the data in the domains
  x.domain(nested_data.map(function(d) { return d.key; }));
  y.domain([0, d3.max(nested_data, function(d) { return +d.value.sumworth; })]);

// // append the rectangles for the bar chart
  svg.selectAll(".bar")
      .data(nested_data)
    .enter().append("rect")
      .attr("class", "bar")
      .attr("x", function(d) { return x(d.key); })
      .attr("width", x.bandwidth())
      .attr("y", function(d) { return y(d.value.sumworth); })
      .attr("height", function(d) { return height - y(d.value.sumworth); });

// // add the x Axis
  svg.append("g")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.axisBottom(x))
		 .selectAll("text")
     .style("text-anchor", "end")
        .attr("dx", ".8em")
  .style("font-size", "15px")
        .attr("dy", ".75em")

// add the y Axis
  svg.append("g")
    .call(d3.axisLeft(y));

svg.append("text")
            .attr("text-anchor", "middle")  // this makes it easy to centre the text as the transform is applied to the anchor
            .attr("transform", "translate("+ margin.right*1.1 +","+(height/2)+")rotate(-90)")  // text is drawn off the screen top left, move down and out and rotate
            .text("Total Worth in Billions");

svg.append("text")
            .attr("text-anchor", "middle")  // this makes it easy to centre the text as the transform is applied to the anchor
            .attr("transform", "translate("+ (width/2) +","+(height+margin.bottom)+")")  // text is drawn off the screen top left, move down and out and rotate
            .text("Year");

});

</script>
<p><a href="https://bl.ocks.org/elt12njo/76b484f5187c7ecfc83070dd81897327/6741bd95237f3ed45867a843e8e5403b90386639">Reference</a></p>
</body>

https://d3js.org/d3.v4.min.js