diff --git a/python/res/enkf/export/summary_observation_collector.py b/python/res/enkf/export/summary_observation_collector.py
index e47aea7e8..6e94d9b19 100644
--- a/python/res/enkf/export/summary_observation_collector.py
+++ b/python/res/enkf/export/summary_observation_collector.py
@@ -34,7 +34,7 @@ def loadObservationData(ert, case_name, keys=None):
         history_length = ert.getHistoryLength()
         dates = [
             observations.getObservationTime(index).datetime()
-            for index in range(1, history_length)
+            for index in range(1, history_length + 1)
         ]
         summary_keys = SummaryObservationCollector.getAllObservationKeys(ert)
         if keys is not None:
@@ -48,7 +48,7 @@ def loadObservationData(ert, case_name, keys=None):
             observation_keys = ert.ensembleConfig().getNode(key).getObservationKeys()
             for obs_key in observation_keys:
                 observation_data = observations[obs_key]
-                for index in range(0, history_length):
+                for index in range(0, history_length + 1):
                     if observation_data.isActive(index):
                         obs_time = observations.getObservationTime(index).datetime()
                         node = observation_data.getNode(index)
diff --git a/tests/res/enkf/export/test_summary_observation_collector.py b/tests/res/enkf/export/test_summary_observation_collector.py
index 051b8f604..0635c3b5d 100644
--- a/tests/res/enkf/export/test_summary_observation_collector.py
+++ b/tests/res/enkf/export/test_summary_observation_collector.py
@@ -1,8 +1,14 @@
+from pathlib import Path
+import pytest
+import shutil
+
+from res.enkf import ResConfig, EnKFMain
+from tests.conftest import source_root
 import os
 from tests import ResTest
 from res.test import ErtTestContext
 from pytest import MonkeyPatch
-
+from ecl.summary import EclSum
 from res.enkf.export import SummaryObservationCollector
 
 
@@ -57,3 +63,43 @@ def test_summary_observation_collector(self):
 
             with self.assertRaises(KeyError):
                 data["FOPR"]
+
+
+test_data_root = Path(source_root()) / "test-data" / "local"
+
+
+@pytest.fixture()
+def setup_snake_oil(tmpdir):
+    with tmpdir.as_cwd():
+        test_data_dir = os.path.join(test_data_root, "snake_oil")
+
+        shutil.copytree(test_data_dir, "test_data")
+        os.chdir("test_data")
+
+        yield ResConfig("snake_oil.ert")
+
+
+def test_summary_obs_last_entry(setup_snake_oil):
+
+    obs_file = Path.cwd() / "observations" / "observations.txt"
+    with obs_file.open(mode="a") as fin:
+        fin.write(
+            """
+            \nSUMMARY_OBSERVATION LAST_DATE
+{
+    VALUE   = 0.01961757428944111;
+    ERROR   = 0.1;
+    DATE    = 23/06/2015;
+    KEY     = FOPR;
+};
+            """
+        )
+
+    ert = EnKFMain(setup_snake_oil)
+
+    summary = EclSum("refcase/SNAKE_OIL_FIELD.UNSMRY")
+    data = SummaryObservationCollector.loadObservationData(ert, "default_0")
+    assert (
+        data["FOPR"].values.tolist()
+        == summary.numpy_vector("FOPRH", report_only=True).tolist()
+    )