diff --git a/src/client/pages/YieldStudyDashboard.tsx b/src/client/pages/YieldStudyDashboard.tsx
index 8871316..3ad93d4 100644
--- a/src/client/pages/YieldStudyDashboard.tsx
+++ b/src/client/pages/YieldStudyDashboard.tsx
@@ -298,11 +298,12 @@ export const YieldStudyDashboard: React.FC = () => {
             const weightInTons = Number(cat.weight) || 0;
             const yieldPerTon = Number(cat.historicalYield) || 0;
             const rawVal = Number(cat.efficiency);
-            const val = !isNaN(rawVal) ? rawVal : 20;
+            const effVal = !isNaN(rawVal) && rawVal > 0 ? rawVal : 80;
 
-            const isLegacyEfficiency = val > 60;
-            const efficiencyDecimal = isLegacyEfficiency ? val / 100 : (100 - val) / 100;
-            const lossFactor = efficiencyDecimal > 0 ? 1 / efficiencyDecimal : 1;
+            // Eficiência de Aplicação (%): 100% = sem perda (lossFactor = 1.0), 80% = 20% perda (lossFactor = 1.25), etc.
+            const effPercent = Math.min(Math.max(effVal, 1), 100);
+            const efficiencyDecimal = effPercent / 100;
+            const lossFactor = 1 / efficiencyDecimal;
 
             // Cálculo por PESO (L/t) - Não usa mais o fator de eficiência/perda
             const litrosPeso = weightInTons * yieldPerTon;
@@ -706,10 +707,10 @@ export const YieldStudyDashboard: React.FC = () => {
                                                                     onChange={e => {
                                                                         const selectedName = e.target.value;
                                                                         const geoType = geometryTypes.find(g => g.name === selectedName);
-                                                                        // Update name and auto-set efficiency (loss) if found
+                                                                        // Update name and auto-set efficiency if found (100% - loss%)
                                                                         updateCategory(cat.id, {
                                                                             name: selectedName,
-                                                                            ...(geoType && { efficiency: geoType.efficiencyLoss || 20 })
+                                                                            ...(geoType && { efficiency: Math.max(10, 100 - (geoType.efficiencyLoss || 20)) })
                                                                         });
                                                                     }}
                                                                 >
@@ -788,11 +789,13 @@ export const YieldStudyDashboard: React.FC = () => {
                                                                 <Ruler size={12} className="absolute left-3 top-1/2 -translate-y-1/2 text-text-muted" />
                                                                 <input
                                                                     type="number"
+                                                                    min="1"
+                                                                    max="100"
                                                                     className="w-full h-11 bg-surface border border-border/40 rounded-xl pl-9 pr-4 text-sm font-black outline-none focus:border-primary transition-all text-blue-600"
                                                                     value={cat.efficiency}
                                                                     onChange={e => updateCategory(cat.id, { efficiency: Number(e.target.value) })}
-                                                                    title="Percentual de Eficiência/Perda (Aplica-se apenas ao cálculo por Área)"
-                                                                    placeholder="20"
+                                                                    title="Eficiência de Aplicação (%) - 100% representa zero perda"
+                                                                    placeholder="80"
                                                                 />
                                                             </div>
                                                         </div>