Updated A LOT

server/rule-catalog.js

@@ -111,8 +111,35 @@ function buildSpecialMethods() {
   ];
 }
 
+// Sage-style 200% declining-balance method codes. The MACRS family (MF/MT/MI) ignores
+// salvage value and recovers the full basis; the standard family (DB/DH/DD) honors salvage
+// (depreciates only down to it). All use a 200% rate and switch to straight-line.
+function build200Methods() {
+  return [
+    method('MF200', 'MACRS', 'MF200 — MACRS Formula, 200% DB (GDS)', 'macrs_declining_balance', {
+      system: 'GDS', rateMultiplier: 2, switchToStraightLine: true, defaultConvention: 'half_year', ignoreSalvage: true
+    }),
+    method('MT200', 'MACRS', 'MT200 — MACRS Tables, 200% DB (GDS)', 'macrs_declining_balance', {
+      system: 'GDS', rateMultiplier: 2, switchToStraightLine: true, defaultConvention: 'half_year', ignoreSalvage: true, usesTables: true
+    }),
+    method('MI200', 'MACRS', 'MI200 — MACRS 200% DB, Indian Reservation', 'macrs_declining_balance', {
+      system: 'GDS', rateMultiplier: 2, switchToStraightLine: true, defaultConvention: 'half_year', ignoreSalvage: true, indianReservation: true
+    }),
+    method('DB200', 'Declining Balance', 'DB200 — 200% Declining Balance to SL (uses book convention)', 'declining_balance', {
+      rateMultiplier: 2, switchToStraightLine: true
+    }),
+    method('DH200', 'Declining Balance', 'DH200 — 200% Declining Balance to SL, Half-Year', 'declining_balance', {
+      rateMultiplier: 2, switchToStraightLine: true, defaultConvention: 'half_year'
+    }),
+    method('DD200', 'Declining Balance', 'DD200 — 200% Declining Balance to SL, Full-Year', 'declining_balance', {
+      rateMultiplier: 2, switchToStraightLine: true, defaultConvention: 'none'
+    })
+  ];
+}
+
 function buildDepreciationMethods() {
   return [
+    ...build200Methods(),
     ...buildMacrsMethods(),
     ...buildAcrsMethods(),
     ...buildGaapMethods(),