diff --git a/pitch-deck/lib/finanzplan/engine.ts b/pitch-deck/lib/finanzplan/engine.ts
index 3df571f..567e848 100644
--- a/pitch-deck/lib/finanzplan/engine.ts
+++ b/pitch-deck/lib/finanzplan/engine.ts
@@ -244,7 +244,7 @@ export async function computeFinanzplan(pool: Pool, scenarioId: string): Promise
     const row = betrieb.find(r => r.row_label === fr.label)
     if (row) {
       const computed = emptyMonthly()
-      for (let m = 1; m <= MONTHS; m++) {
+      for (let m = FOUNDING_MONTH; m <= MONTHS; m++) {
         computed[`m${m}`] = Math.round((fr.source[`m${m}`] || 0) * fr.perUnit)
       }
       await pool.query('UPDATE fp_betriebliche_aufwendungen SET values = $1 WHERE id = $2', [JSON.stringify(computed), row.id])
@@ -256,7 +256,7 @@ export async function computeFinanzplan(pool: Pool, scenarioId: string): Promise
   const bgRow = betrieb.find(r => r.row_label.includes('Berufsgenossenschaft'))
   if (bgRow) {
     const computed = emptyMonthly()
-    for (let m = 1; m <= MONTHS; m++) {
+    for (let m = FOUNDING_MONTH; m <= MONTHS; m++) {
       computed[`m${m}`] = Math.round((totalBrutto[`m${m}`] || 0) * 0.0277)
     }
     await pool.query('UPDATE fp_betriebliche_aufwendungen SET values = $1 WHERE id = $2', [JSON.stringify(computed), bgRow.id])
@@ -267,7 +267,7 @@ export async function computeFinanzplan(pool: Pool, scenarioId: string): Promise
   const marketingRow = betrieb.find(r => r.row_label.includes('Allgemeine Marketingkosten'))
   if (marketingRow) {
     const computed = emptyMonthly()
-    for (let m = 1; m <= MONTHS; m++) {
+    for (let m = FOUNDING_MONTH; m <= MONTHS; m++) {
       computed[`m${m}`] = Math.round((totalRevenue[`m${m}`] || 0) * 0.10)
     }
     await pool.query('UPDATE fp_betriebliche_aufwendungen SET values = $1 WHERE id = $2', [JSON.stringify(computed), marketingRow.id])
@@ -284,7 +284,7 @@ export async function computeFinanzplan(pool: Pool, scenarioId: string): Promise
   const serverRow = betrieb.find(r => r.row_label === 'Serverkosten Cloud (F)' || r.row_label === 'Serverkosten (Cloud)')
   if (serverRow) {
     const computed = emptyMonthly()
-    for (let m = 1; m <= MONTHS; m++) {
+    for (let m = FOUNDING_MONTH; m <= MONTHS; m++) {
       computed[`m${m}`] = Math.round((totalKunden[`m${m}`] || 0) * 50 + 300)
     }
     await pool.query('UPDATE fp_betriebliche_aufwendungen SET values = $1 WHERE id = $2', [JSON.stringify(computed), serverRow.id])
@@ -313,7 +313,7 @@ export async function computeFinanzplan(pool: Pool, scenarioId: string): Promise
       !r.is_sum_row && !r.row_label.includes('Summe') && !r.row_label.includes('SUMME')
     )
     const computed = emptyMonthly()
-    for (let m = 1; m <= MONTHS; m++) {
+    for (let m = FOUNDING_MONTH; m <= MONTHS; m++) {
       const rev = totalRevenue[`m${m}`] || 0
       const mat = totalMaterial[`m${m}`] || 0
       const pers = totalPersonal[`m${m}`] || 0