          .call(xAxis);
        
        d3.select("svg").selectAll("circle.median")
          .data(data)
          .enter()
          .append("circle")
            .attr("class", "tweets")
            .attr("r", 5)
            .attr("cx", d => xScale(d.day))
            .attr("cy", d => yScale(d.median))
            .style("fill", "darkgray");
        
        d3.select("svg").selectAll("g.box")
          .data(data).enter()
          .append("g")
            .attr("class", "box")
            .attr("trans