function chart(){
let svg = d3
.create("svg")
.attr("width", dimensions.width + margins.left+ margins.right)
.attr("height", dimensions.height+margins.top+margins.bottom);
svg.style("background-color","#f2f2f2");
yearAxis({svg:svg});
yAxis({svg:svg});
zeroLine({svg:svg});
forecastBox({svg:svg});
let opacity = "0.3"
line({svg:svg, variable:"China Delta", color:"red"});
line({svg:svg, variable:"Russia Delta"});
line({svg:svg, variable:"Vietnam Delta", opacity:opacity});
line({svg:svg, variable:"United States Delta",opacity:opacity});
line({svg:svg, variable:"Brazil Delta", opacity:opacity});
return svg.node();
}