diff --git a/test/plots/availability.ts b/test/plots/availability.ts
index 4764e34f34..05ab7203c5 100644
--- a/test/plots/availability.ts
+++ b/test/plots/availability.ts
@@ -3,7 +3,6 @@ import * as d3 from "d3";
 
 export async function availability() {
   const data = await d3.csv<any>("data/availability.csv", d3.autoType);
-  const sum = (d) => (d.length ? d3.sum(d) : NaN); // force gaps
   return Plot.plot({
     height: 180,
     marks: [
@@ -11,7 +10,6 @@ export async function availability() {
         x: "date",
         y: "value",
         interval: "day",
-        reduce: sum,
         curve: "step",
         fill: "#f2f2fe"
       }),
@@ -19,7 +17,6 @@ export async function availability() {
         x: "date",
         y: "value",
         interval: "day",
-        reduce: sum,
         curve: "step"
       }),
       Plot.ruleY([0])