diff --git a/src/main/java/com/goi/erp/repository/CustomerRepository.java b/src/main/java/com/goi/erp/repository/CustomerRepository.java
index b01a853..4ab3a3a 100644
--- a/src/main/java/com/goi/erp/repository/CustomerRepository.java
+++ b/src/main/java/com/goi/erp/repository/CustomerRepository.java
@@ -30,29 +30,36 @@ public interface CustomerRepository extends JpaRepository<Customer, Long> {
     // 오늘 추가된 고객 수: cus_contract_date = 오늘
     long countByCusContractDate(LocalDate cusContractDate);
 
-    // 날짜별 활성 고객 수 + 신규/해지 (선그래프·막대그래프용).
-    //  - active_count  = cus_status='A' 이고 그 날짜에 계약기간 안에 있던 고객 수 (날짜로 과거 재구성)
-    //  - added_count   = 그 날짜에 계약 시작 (cus_contract_date = D)
-    //  - removed_count = 그 날짜에 해지       (cus_terminated_date = D)
-    //  - generate_series 로 [startDate, endDate] 각 날짜 생성 → 빈 날도 0
+    // 날짜별 활성 곳 수 + 일별 신규/해지 — "현재 기준 역산(reverse-calc)" 모델.
+    //  - 기준점: 오늘 활성 = cus_status='A' 수 (신뢰 기준, 카드와 동일)
+    //  - 과거 D의 활성 = 오늘 활성 − (D 이후 신규 계약) + (D 이후 해지)
+    //      · D 이후 신규는 D 시점엔 아직 없었으니 빼고
+    //      · D 이후 해지는 D 시점엔 아직 있었으니 더함
+    //  - added/removed 는 effective date(cus_contract_date / cus_terminated_date) 기준 일별 이벤트
+    //  - active(D) = active(D-1) + added(D) − removed(D) 가 정확히 성립.
+    //    소급(백데이트)된 건도 매 조회마다 현재 날짜값으로 재계산되어 effective date 위치에 반영됨.
     //  - return: [0]=날짜(date), [1]=active(bigint), [2]=added(bigint), [3]=removed(bigint)
     @Query(value = """
-            SELECT CAST(series.day AS date) AS day,
-                   (SELECT COUNT(*) FROM crm.customer c
-                     WHERE c.cus_status = 'A'
-                       AND c.cus_contract_date <= CAST(series.day AS date)
-                       AND (c.cus_terminated_date IS NULL OR c.cus_terminated_date > CAST(series.day AS date))
+            SELECT days.day AS day,
+                   ( (SELECT COUNT(*) FROM crm.customer WHERE cus_status = 'A')
+                     - (SELECT COUNT(*) FROM crm.customer
+                          WHERE cus_contract_date > days.day
+                            AND cus_contract_date <= CAST(:endDate AS date))
+                     + (SELECT COUNT(*) FROM crm.customer
+                          WHERE cus_terminated_date > days.day
+                            AND cus_terminated_date <= CAST(:endDate AS date))
                    ) AS active_count,
-                   (SELECT COUNT(*) FROM crm.customer a
-                     WHERE a.cus_contract_date = CAST(series.day AS date)
-                   ) AS added_count,
-                   (SELECT COUNT(*) FROM crm.customer r
-                     WHERE r.cus_terminated_date = CAST(series.day AS date)
-                   ) AS removed_count
-            FROM generate_series(CAST(:startDate AS timestamp),
-                                 CAST(:endDate   AS timestamp),
-                                 INTERVAL '1 day') AS series(day)
-            ORDER BY series.day
+                   (SELECT COUNT(*) FROM crm.customer
+                     WHERE cus_contract_date = days.day) AS added_count,
+                   (SELECT COUNT(*) FROM crm.customer
+                     WHERE cus_terminated_date = days.day) AS removed_count
+            FROM (
+                SELECT CAST(series.day AS date) AS day
+                FROM generate_series(CAST(:startDate AS timestamp),
+                                     CAST(:endDate   AS timestamp),
+                                     INTERVAL '1 day') AS series(day)
+            ) days
+            ORDER BY days.day
             """, nativeQuery = true)
     List<Object[]> findActiveCustomerTrend(@Param("startDate") LocalDate startDate,
                                            @Param("endDate") LocalDate endDate);