From 898b540b3f47b455115f5c9a65aa93c334e565d8 Mon Sep 17 00:00:00 2001
From: Carlos Escalante <cescalante2988@gmail.com>
Date: Wed, 1 Apr 2026 10:06:08 -0600
Subject: [PATCH] Fix roiEarned crash when chart data has fewer than 12 entries

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 frontend/src/pages/Pensions.tsx | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/frontend/src/pages/Pensions.tsx b/frontend/src/pages/Pensions.tsx
index 8a9bfe7..29d3043 100644
--- a/frontend/src/pages/Pensions.tsx
+++ b/frontend/src/pages/Pensions.tsx
@@ -324,15 +324,18 @@ export default function Pensions() {
         // Use real rendimientos from the API
         acc[key] = Math.round(snap.rendimientos);
       } else {
-        // Fallback: approximate from hardcoded data
+        // Fallback: approximate from chart data
         const fund = FUNDS[key];
-        if (fund.isDividend) {
+        const len = chartData.length;
+        if (len >= 2 && fund.isDividend) {
           acc[key] = Math.max(0, Math.round(
-            chartData[11][key] - chartData[10][key] - fund.monthlyContribution,
+            chartData[len - 1][key] - chartData[len - 2][key] - fund.monthlyContribution,
           ));
-        } else {
+        } else if (len > 0) {
           const activeMonths = chartData.filter((d) => d[key] > 0).length;
           acc[key] = Math.round(fund.startBalance * (fund.annualRate / 100) * (activeMonths / 12));
+        } else {
+          acc[key] = 0;
         }
       }
       return acc;