Index: node_modules/d3-shape/src/offset/expand.js
===================================================================
--- node_modules/d3-shape/src/offset/expand.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
+++ node_modules/d3-shape/src/offset/expand.js	(revision e4c61dd6cd86e06265bc2bd91adba84a0f04044a)
@@ -0,0 +1,10 @@
+import none from "./none.js";
+
+export default function(series, order) {
+  if (!((n = series.length) > 0)) return;
+  for (var i, n, j = 0, m = series[0].length, y; j < m; ++j) {
+    for (y = i = 0; i < n; ++i) y += series[i][j][1] || 0;
+    if (y) for (i = 0; i < n; ++i) series[i][j][1] /= y;
+  }
+  none(series, order);
+}