Irregular Histogram

<!DOCTYPE html>
<meta charset="utf-8">
<style>

svg {
  font: 10px sans-serif;
}

rect {
  fill: steelblue;
}

.axis path, .axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

</style>
<body>
<script src="//d3js.org/d3.v3.min.js"></script>
<script>

var margin = {top: 10, right: 20, bottom: 20, left: 60},
    width = 960 - margin.left - margin.right,
    height = 500 - margin.top - margin.bottom;

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 + ")");

var x = d3.scale.linear()
    .range([0, width]);

var y = d3.scale.linear()
    .range([height, 0]);

d3.csv("income.csv", function(error, bins) {
  if (error) throw error;

// Coerce types.
  bins.forEach(function(bin) {
    bin.Income = +bin.Income;
    bin.People = +bin.People;
  });

// Normalize each bin to so that height = quantity/width;
  // see https://en.wikipedia.org/wiki/Histogram#Examples
  for (var i = 1, n = bins.length, bin; i < n; i++) {
    bin = bins[i];
    bin.offset = bins[i - 1].Income;
    bin.width = bin.Income - bin.offset;
    bin.height = bin.People / bin.width;
  }

// Drop the first bin, since it's incorporated into the next.
  bins.shift();

// Set the scale domain.
  x.domain([0, d3.max(bins.map(function(d) { return d.offset + d.width; }))]);
  y.domain([0, d3.max(bins.map(function(d) { return d.height; }))]);

// Add the bins.
  svg.selectAll(".bin")
      .data(bins)
    .enter().append("rect")
      .attr("class", "bin")
      .attr("x", function(d) { return x(d.offset); })
      .attr("width", function(d) { return x(d.width) - 1; })
      .attr("y", function(d) { return y(d.height); })
      .attr("height", function(d) { return height - y(d.height); });

svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(d3.svg.axis()
      .scale(x)
      .orient("bottom"));

svg.append("g")
      .attr("class", "y axis")
      .call(d3.svg.axis()
      .scale(y)
      .orient("left"));
});

</script>

https://d3js.org/d3.v3.min.js