diff --git a/src/app/components/FireCalculatorForm.tsx b/src/app/components/FireCalculatorForm.tsx
index d6bf676..3c4e4ec 100644
--- a/src/app/components/FireCalculatorForm.tsx
+++ b/src/app/components/FireCalculatorForm.tsx
@@ -175,7 +175,6 @@ export default function FireCalculatorForm() {
         // Simulate retirement phase for chart data (using 4% withdrawal adjusted for inflation)
         let simulationCapital = currentCapital;
         let simulationAge = retirementAge;
-        let simulationAllowance = finalInflationAdjustedAllowance!;
 
         // Mark retirement phase in existing data
         yearlyData.forEach((data) => {
@@ -214,7 +213,6 @@ export default function FireCalculatorForm() {
 
       while (age < lifeExpectancy && iterations < maxIterations) {
         // Simulate one year of saving and growth
-        let yearStartCapital = currentCapital;
         for (let month = 0; month < 12; month++) {
           currentCapital += monthlySavings;
           currentCapital *= 1 + monthlyGrowthRate;
@@ -238,16 +236,12 @@ export default function FireCalculatorForm() {
 
         // Simulate retirement phase to check sufficiency
         while (testAge < lifeExpectancy) {
-          let yearlyStartCapital = testCapital;
-          let yearlyGrowth = 0;
-          let yearlyWithdrawal = 0;
+          const yearlyStartCapital = testCapital;
 
           for (let month = 0; month < 12; month++) {
-            let withdrawal = testAllowance;
-            yearlyWithdrawal += withdrawal;
+            const withdrawal = testAllowance;
             testCapital -= withdrawal;
-            let growth = testCapital * monthlyGrowthRate;
-            yearlyGrowth += growth;
+            const growth = testCapital * monthlyGrowthRate;
             testCapital += growth; // Apply growth *after* withdrawal for the month
             testAllowance *= 1 + monthlyInflationRate; // Inflate allowance for next month
           }
diff --git a/src/components/ui/chart.tsx b/src/components/ui/chart.tsx
index a05c72b..ddb4e09 100644
--- a/src/components/ui/chart.tsx
+++ b/src/components/ui/chart.tsx
@@ -1,3 +1,4 @@
+/* eslint-disable @typescript-eslint/no-unsafe-assignment */
 "use client";
 
 import * as React from "react";
@@ -8,15 +9,16 @@ import { cn } from "@/lib/utils";
 // Format: { THEME_NAME: CSS_SELECTOR }
 const THEMES = { light: "", dark: ".dark" } as const;
 
-export type ChartConfig = {
-  [k in string]: {
+export type ChartConfig = Record<
+  string,
+  {
     label?: React.ReactNode;
     icon?: React.ComponentType;
   } & (
     | { color?: string; theme?: never }
     | { color?: never; theme: Record<keyof typeof THEMES, string> }
-  );
-};
+  )
+>;
 
 type ChartContextProps = {
   config: ChartConfig;
@@ -47,7 +49,7 @@ function ChartContainer({
   >["children"];
 }) {
   const uniqueId = React.useId();
-  const chartId = `chart-${id || uniqueId.replace(/:/g, "")}`;
+  const chartId = `chart-${id ?? uniqueId.replace(/:/g, "")}`;
 
   return (
     <ChartContext.Provider value={{ config }}>
@@ -71,7 +73,7 @@ function ChartContainer({
 
 const ChartStyle = ({ id, config }: { id: string; config: ChartConfig }) => {
   const colorConfig = Object.entries(config).filter(
-    ([, config]) => config.theme || config.color,
+    ([, config]) => config.theme ?? config.color,
   );
 
   if (!colorConfig.length) {
@@ -88,7 +90,7 @@ ${prefix} [data-chart=${id}] {
 ${colorConfig
   .map(([key, itemConfig]) => {
     const color =
-      itemConfig.theme?.[theme as keyof typeof itemConfig.theme] ||
+      itemConfig.theme?.[theme as keyof typeof itemConfig.theme] ??
       itemConfig.color;
     return color ? `  --color-${key}: ${color};` : null;
   })
@@ -134,11 +136,11 @@ function ChartTooltipContent({
     }
 
     const [item] = payload;
-    const key = `${labelKey || item?.dataKey || item?.name || "value"}`;
+    const key = `${labelKey ?? item?.dataKey ?? item?.name ?? "value"}`;
     const itemConfig = getPayloadConfigFromPayload(config, item, key);
     const value =
       !labelKey && typeof label === "string"
-        ? config[label as keyof typeof config]?.label || label
+        ? (config[label]?.label ?? label)
         : itemConfig?.label;
 
     if (labelFormatter) {
@@ -180,9 +182,11 @@ function ChartTooltipContent({
       {!nestLabel ? tooltipLabel : null}
       <div className="grid gap-1.5">
         {payload.map((item, index) => {
-          const key = `${nameKey || item.name || item.dataKey || "value"}`;
+          const key = `${nameKey ?? item.name ?? item.dataKey ?? "value"}`;
           const itemConfig = getPayloadConfigFromPayload(config, item, key);
-          const indicatorColor = color || item.payload.fill || item.color;
+          const indicatorColor: string | undefined =
+            // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+            color ?? item.payload.fill ?? item.color;
 
           return (
             <div
@@ -193,6 +197,7 @@ function ChartTooltipContent({
               )}
             >
               {formatter && item?.value !== undefined && item.name ? (
+                // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
                 formatter(item.value, item.name, item, index, item.payload)
               ) : (
                 <>
@@ -229,7 +234,7 @@ function ChartTooltipContent({
                     <div className="grid gap-1.5">
                       {nestLabel ? tooltipLabel : null}
                       <span className="text-muted-foreground">
-                        {itemConfig?.label || item.name}
+                        {itemConfig?.label ?? item.name}
                       </span>
                     </div>
                     {item.value && (
@@ -276,7 +281,8 @@ function ChartLegendContent({
       )}
     >
       {payload.map((item) => {
-        const key = `${nameKey || item.dataKey || "value"}`;
+        // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
+        const key = `${nameKey ?? item.dataKey ?? "value"}`;
         const itemConfig = getPayloadConfigFromPayload(config, item, key);
 
         return (
@@ -338,9 +344,7 @@ function getPayloadConfigFromPayload(
     ] as string;
   }
 
-  return configLabelKey in config
-    ? config[configLabelKey]
-    : config[key as keyof typeof config];
+  return configLabelKey in config ? config[configLabelKey] : config[key];
 }
 
 export {