diff --git a/src/climatevision/generator/entries.py b/src/climatevision/generator/entries.py
index 013c81fe..23fab3f4 100644
--- a/src/climatevision/generator/entries.py
+++ b/src/climatevision/generator/entries.py
@@ -114,6 +114,7 @@ class Entries:
     m_population_sta: int  # population of state in 2018
     m_year_target: int
     m_year_today: int
+    m_year_ref: int  # reference year for data (i.e RefData.year_ref() )
     r_area_m2: float
     r_area_m2_1flat: float
     r_area_m2_2flat: float
diff --git a/src/climatevision/generator/makeentries.py b/src/climatevision/generator/makeentries.py
index 32e720ed..53a83503 100644
--- a/src/climatevision/generator/makeentries.py
+++ b/src/climatevision/generator/makeentries.py
@@ -594,6 +594,7 @@ def compute_efactor_from_n2o(
         m_population_sta=m_population_sta,
         m_year_target=m_year_target,
         m_year_today=m_year_today,
+        m_year_ref=data.year_ref(),
         r_area_m2=r_area_m2,
         r_area_m2_1flat=r_area_m2_1flat,
         r_area_m2_2flat=r_area_m2_2flat,
diff --git a/tests/end_to_end_expected/entries_03159016_2035.json b/tests/end_to_end_expected/entries_03159016_2035.json
index 34f55eda..413ee715 100644
--- a/tests/end_to_end_expected/entries_03159016_2035.json
+++ b/tests/end_to_end_expected/entries_03159016_2035.json
@@ -108,6 +108,7 @@
     "m_population_sta": 7982448,
     "m_year_target": 2035,
     "m_year_today": 2022,
+    "m_year_ref": 2018,
     "r_area_m2": 5125600.0,
     "r_area_m2_1flat": 1238094.45,
     "r_area_m2_2flat": 513206.64,