diff --git a/c3.js b/c3.js
index 052a440..818430c 100644
--- a/c3.js
+++ b/c3.js
@@ -795,7 +795,7 @@
                 var data = filterRemoveNull(d.values), x0, y0;
                 if (isLineType(d)) {
                     isSplineType(d) ? line.interpolate("cardinal") : line.interpolate("linear");
-                    return Object.keys(__data_regions).length > 0 ? lineWithRegions(data, x, getYScale(d.id), __data_regions[d.id]) : line(data);
+                    return __data_regions[d.id] ? lineWithRegions(data, x, getYScale(d.id), __data_regions[d.id]) : line(data);
                 } else {
                     x0 = x(data[0].x);
                     y0 = getYScale(d.id)(data[0].value);
diff --git a/c3.min.js b/c3.min.js
index c9fa06a..a9b4d3a 100644
--- a/c3.min.js
+++ b/c3.min.js
@@ -57,9 +57,9 @@ Oa=e(["axis","x","default"],null),dd=e(["axis","x","label"],null),Jc=e(["axis","
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 a)return a[b];-1===c.indexOf(b)&&c.push(b);return d[c.indexOf(b)%d.length]}}(qd,rd),Ec=function(){var a=[[d.time.format("%Y/%-m/%-d"),function(){return!0}],[d.time.format("%-m/%-d"),function(a){return a.getMonth()}],[d.time.format("%-m/%-d"),function(a){return 1!==a.getDate()}],[d.time.format("%-m/%-d"),function(a){return a.getDay()&&1!==a.getDate()}],[d.time.format("%I %p"),function(a){return a.getHours()}],[d.time.format("%I:%M"),function(a){return a.getMinutes()}],[d.time.format(":%S"),function(a){return a.getSeconds()}],
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-(f?0:r)+","+(f?10:0)+")"},x:function(){return"translate(0,"+u+")"},subx:function(){return"translate(0,"+ma+")"}},ld=function(){var a=d.svg.line().x(f?function(a){return D(a.id)(a.value)}:cb).y(f?cb:function(a){return D(a.id)(a.value)});return function(b){var c=lc(b.values),d;if(ub(b))return"spline"===fa["string"===typeof b?b:b.id]?a.interpolate("cardinal"):a.interpolate("linear"),0<Object.keys(uc).length?Xc(c,l,D(b.id),uc[b.id]):a(c);d=l(c[0].x);b=D(b.id)(c[0].value);return f?"M "+b+" "+d:"M "+d+
-" "+b}}(),md=function(){var a=d.svg.line().x(function(a){return ba(a.x)}).y(function(a){return R(a.id)(a.value)});return function(b){var c=lc(b.values);return ub(b)?a(c):"M "+ba(c[0].x)+" "+R(b.id)(c[0].value)}}(),F=d.svg.brush().on("brush",function(){B({withTransition:!1,withY:!1,withSubchart:!1,withUpdateXDomain:!0})}),G=d.behavior.zoom().on("zoomstart",function(){G.altDomain=d.event.sourceEvent.altKey?l.orgDomain():null}).on("zoom",pa?nd:null);F.update=function(){x&&x.select(".x.brush").call(this);
-return this};G.orgScaleExtent=function(){var a=tc?tc:[1,10];return[a[0],Math.max(va()/a[1],a[1])]};G.updateScaleExtent=function(){var a=l.orgDomain(),a=(a[1]-a[0])/(U[1]-U[0]),b=this.orgScaleExtent();this.scaleExtent([b[0]*a,b[1]*a]);return this};var Ma,eb,h,x,xa,X,db,bb=null,pb=null,U;g.focus=function(a){g.defocus();d.selectAll(Ra(a)).filter(function(a){return rb(a.id)}).classed("focused",!0).transition().duration(100).style("opacity",1)};g.defocus=function(a){d.selectAll(Ra(a)).filter(function(a){return rb(a.id)}).classed("focused",
+(f?0:r)+","+(f?10:0)+")"},x:function(){return"translate(0,"+u+")"},subx:function(){return"translate(0,"+ma+")"}},ld=function(){var a=d.svg.line().x(f?function(a){return D(a.id)(a.value)}:cb).y(f?cb:function(a){return D(a.id)(a.value)});return function(b){var c=lc(b.values),d;if(ub(b))return"spline"===fa["string"===typeof b?b:b.id]?a.interpolate("cardinal"):a.interpolate("linear"),uc[b.id]?Xc(c,l,D(b.id),uc[b.id]):a(c);d=l(c[0].x);b=D(b.id)(c[0].value);return f?"M "+b+" "+d:"M "+d+" "+b}}(),md=function(){var a=
+d.svg.line().x(function(a){return ba(a.x)}).y(function(a){return R(a.id)(a.value)});return function(b){var c=lc(b.values);return ub(b)?a(c):"M "+ba(c[0].x)+" "+R(b.id)(c[0].value)}}(),F=d.svg.brush().on("brush",function(){B({withTransition:!1,withY:!1,withSubchart:!1,withUpdateXDomain:!0})}),G=d.behavior.zoom().on("zoomstart",function(){G.altDomain=d.event.sourceEvent.altKey?l.orgDomain():null}).on("zoom",pa?nd:null);F.update=function(){x&&x.select(".x.brush").call(this);return this};G.orgScaleExtent=
+function(){var a=tc?tc:[1,10];return[a[0],Math.max(va()/a[1],a[1])]};G.updateScaleExtent=function(){var a=l.orgDomain(),a=(a[1]-a[0])/(U[1]-U[0]),b=this.orgScaleExtent();this.scaleExtent([b[0]*a,b[1]*a]);return this};var Ma,eb,h,x,xa,X,db,bb=null,pb=null,U;g.focus=function(a){g.defocus();d.selectAll(Ra(a)).filter(function(a){return rb(a.id)}).classed("focused",!0).transition().duration(100).style("opacity",1)};g.defocus=function(a){d.selectAll(Ra(a)).filter(function(a){return rb(a.id)}).classed("focused",
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 a).remove(),gb(g.data.targets));0<g.data.targets.length&&B()};g.selected=function(a){a=n(a)?"-"+a:"";return d.merge(h.selectAll(".-shapes"+a).selectAll(".-shape").filter(function(){return d.select(this).classed(ia)}).map(function(a){return a.map(function(a){return a.__data__})}))};g.select=function(a,b,c){ga&&h.selectAll(".-shapes").selectAll(".-shape").each(function(e,f){var g="circle"===this.nodeName?hc:Wc,h="circle"===this.nodeName?vb:jc;0<=b.indexOf(f)?ra(e)&&(qa||t(a)||0<=a.indexOf(e.id))&&g(d.select(this).classed(ia,