diff --git a/App.tsx b/App.tsx
index 4695390..cf6b54a 100644
--- a/App.tsx
+++ b/App.tsx
@@ -596,9 +596,10 @@ const App: React.FC = () => {
   const gridContext = useMemo(() => {
     if (rawData.length === 0) return { minWeek: 1, maxWeek: 53, currentYear: new Date().getFullYear() };
 
-    const currentYear = Math.max(...rawData.map(r => r.year));
+    const currentYear = rawData.reduce((max, r) => Math.max(max, r.year), 0);
     const currentYearData = rawData.filter(r => r.year === currentYear);
-    const maxWeek = Math.max(...currentYearData.map(r => r.week).filter(Boolean));
+    const maxWeek = currentYearData.map(r => r.week).filter((w): w is number => w !== undefined)
+      .reduce((max, w) => Math.max(max, w), 0);
 
     return { minWeek: 1, maxWeek: maxWeek || 53, currentYear };
   }, [rawData]);
diff --git a/components/mkt/MasterTable.tsx b/components/mkt/MasterTable.tsx
index 13bb6dd..dc62551 100644
--- a/components/mkt/MasterTable.tsx
+++ b/components/mkt/MasterTable.tsx
@@ -158,19 +158,20 @@ export const MasterTable: React.FC<MasterTableProps> = ({ products, includeCOGS,
             </tr>
 
             {/* Product Rows */}
-            {sortedProducts.map((product) => {
-              const metrics = calculateProductMetrics(product, includeCOGS);
-              
-              // Data bar width calculation (relative to max sales)
-              const maxSales = Math.max(...products.map(p => p.grossSales));
-              const salesBarWidth = `${(product.grossSales / maxSales) * 100}%`;
+            {(() => {
+              const maxSales = products.reduce((max, p) => Math.max(max, p.grossSales), 0);
+              return sortedProducts.map((product) => {
+                const metrics = calculateProductMetrics(product, includeCOGS);
+                
+                // Data bar width calculation (relative to max sales)
+                const salesBarWidth = maxSales > 0 ? `${(product.grossSales / maxSales) * 100}%` : '0%';
 
-              return (
-                <tr 
-                  key={product.id} 
-                  className="hover:bg-[#1A1E2A] transition-colors cursor-pointer group"
-                  onClick={() => onProductClick(product)}
-                >
+                return (
+                  <tr 
+                    key={product.id} 
+                    className="hover:bg-[#1A1E2A] transition-colors cursor-pointer group"
+                    onClick={() => onProductClick(product)}
+                  >
                   <td className="px-6 py-4 whitespace-normal min-w-[250px] max-w-[300px]">
                     <div className="font-medium text-slate-200 group-hover:text-indigo-400 transition-colors line-clamp-2" title={product.name}>{product.name}</div>
                     <div className="text-xs text-slate-500 font-mono mt-0.5">{product.sku} | {product.asin}</div>
@@ -230,7 +231,7 @@ export const MasterTable: React.FC<MasterTableProps> = ({ products, includeCOGS,
                   </td>
                 </tr>
               );
-            })}
+            })})()}
           </tbody>
         </table>
       </div>
diff --git a/services/dataProcessor.ts b/services/dataProcessor.ts
index 561b0a0..55c8992 100644
--- a/services/dataProcessor.ts
+++ b/services/dataProcessor.ts
@@ -2461,9 +2461,12 @@ export const calculateVelocityMap = (data: SalesRecord[]): Map<string, number> =
     const validYears = data.map(r => r.year).filter(y => y > 0);
     if (validYears.length === 0) return new Map();
 
-    const latestYear = Math.max(...validYears);
+    const latestYear = validYears.reduce((a, b) => Math.max(a, b), 0);
     const yearData = data.filter(r => r.year === latestYear);
-    const latestWeek = yearData.length > 0 ? Math.max(...yearData.map(r => r.week).filter(w => w !== undefined) as number[]) : 0;
+    const latestWeek = yearData.length > 0 
+        ? (yearData.map(r => r.week).filter(w => w !== undefined) as number[])
+            .reduce((a, b) => Math.max(a, b), 0)
+        : 0;
 
     const last4WeeksKeys = new Set<string>();
     for (let i = 0; i < 4; i++) {