diff --git a/decoimpact/business/entities/rule_based_model.py b/decoimpact/business/entities/rule_based_model.py
index c805f100..5dbad9e0 100644
--- a/decoimpact/business/entities/rule_based_model.py
+++ b/decoimpact/business/entities/rule_based_model.py
@@ -97,7 +97,6 @@ def initialize(self, logger: ILogger) -> None:
         self._output_dataset = _du.create_composed_dataset(
             self._input_datasets, self._make_output_variables_list(), self._mappings
         )
-
         self._rule_processor = RuleProcessor(self._rules, self._output_dataset)
         success = self._rule_processor.initialize(logger)
 
@@ -109,7 +108,9 @@ def execute(self, logger: ILogger) -> None:
         if self._rule_processor is None:
             raise RuntimeError("Processor is not set, please initialize model.")
 
-        self._rule_processor.process_rules(self._output_dataset, logger)
+        self._output_dataset = self._rule_processor.process_rules(
+            self._output_dataset, logger
+        )
 
     def finalize(self, logger: ILogger) -> None:
         """Finalizes the model"""
diff --git a/decoimpact/business/entities/rule_processor.py b/decoimpact/business/entities/rule_processor.py
index 7070ff49..5e608547 100644
--- a/decoimpact/business/entities/rule_processor.py
+++ b/decoimpact/business/entities/rule_processor.py
@@ -62,7 +62,9 @@ def initialize(self, logger: ILogger) -> bool:
 
         return success
 
-    def process_rules(self, output_dataset: _xr.Dataset, logger: ILogger) -> None:
+    def process_rules(
+        self, output_dataset: _xr.Dataset, logger: ILogger
+    ) -> _xr.Dataset:
         """Processes the rules defined in the initialize method
         and adds the results to the provided output_dataset.
 
@@ -89,7 +91,16 @@ def process_rules(self, output_dataset: _xr.Dataset, logger: ILogger) -> None:
                     rule_result.dims,
                     rule_result.values,
                     rule_result.attrs,
+                    rule_result.coords,
                 )
+                for coord_key in rule_result.coords:
+                    # the coord_key is overwritten in case we don't have the if 
+                    # statement below
+                    if coord_key not in output_dataset.coords:
+                        output_dataset = output_dataset.assign_coords(
+                            {coord_key: rule_result[coord_key]}
+                        )
+        return output_dataset
 
     def _create_rule_sets(
         self,
diff --git a/decoimpact/business/entities/rules/time_aggregation_rule.py b/decoimpact/business/entities/rules/time_aggregation_rule.py
index 27ba39ba..f0d2cb3e 100644
--- a/decoimpact/business/entities/rules/time_aggregation_rule.py
+++ b/decoimpact/business/entities/rules/time_aggregation_rule.py
@@ -81,6 +81,12 @@ def execute(self, value_array: _xr.DataArray, logger: ILogger) -> _xr.DataArray:
             if value:
                 result[result_time_dim_name].attrs[key] = value
 
+        result = result.assign_coords({
+            result_time_dim_name: result[result_time_dim_name]
+        })
+        result[result_time_dim_name].attrs['long_name'] = result_time_dim_name
+        result[result_time_dim_name].attrs['standard_name'] = result_time_dim_name
+
         return result
 
     def _perform_operation(self, aggregated_values: DataArrayResample) -> _xr.DataArray:
diff --git a/tests/business/entities/test_rule_processor.py b/tests/business/entities/test_rule_processor.py
index e7f1abd1..3625eb53 100644
--- a/tests/business/entities/test_rule_processor.py
+++ b/tests/business/entities/test_rule_processor.py
@@ -18,7 +18,9 @@
     IMultiArrayBasedRule,
 )
 from decoimpact.business.entities.rules.i_rule import IRule
+from decoimpact.business.entities.rules.time_aggregation_rule import TimeAggregationRule
 from decoimpact.crosscutting.i_logger import ILogger
+from decoimpact.data.api.i_time_aggregation_rule_data import ITimeAggregationRuleData
 
 
 def _create_test_rules() -> List[IRule]:
@@ -384,6 +386,54 @@ def test_process_rules_throws_exception_for_unsupported_rule():
     assert exception_raised.args[0] == expected_message
 
 
+def test_process_rules_copies_multi_coords_correctly():
+    """Tests if during processing the coords are copied to the output array
+    and there are no duplicates."""
+
+    # Arrange
+    output_dataset = _xr.Dataset()
+    output_dataset["test"] = _xr.DataArray([32, 94, 9])
+
+    logger = Mock(ILogger)
+    rule = Mock(IArrayBasedRule)
+    rule_2 = Mock(IArrayBasedRule)
+
+    result_array = _xr.DataArray([27, 45, 93])
+    result_array = result_array.assign_coords({"test": _xr.DataArray([2, 4, 5])})
+
+    result_array_2 = _xr.DataArray([1, 2, 93])
+    result_array_2 = result_array.assign_coords({"test": _xr.DataArray([2, 4, 5])})
+
+    rule.input_variable_names = ["test"]
+    rule.output_variable_name = "output"
+    rule.execute.return_value = result_array
+
+    rule_2.input_variable_names = ["test"]
+    rule_2.output_variable_name = "output_2"
+    rule_2.execute.return_value = result_array_2
+
+    processor = RuleProcessor([rule, rule_2], output_dataset)
+
+    # Act
+    assert processor.initialize(logger)
+    result_dataset = processor.process_rules(output_dataset, logger)
+
+    # Assert
+    assert "test" in result_dataset.coords
+    # compare coords at the level of variable
+    result_array_coords = result_array.coords["test"]
+    result_output_var_coords = result_dataset.output.coords["test"]  # output variable
+    assert (result_output_var_coords == result_array_coords).all()
+
+    # compare coords at the level of dataset /
+    # check if the coordinates are correctly copied to the dataset
+    result_dataset_coords = result_dataset.coords["test"]
+    assert (result_output_var_coords == result_dataset_coords).all()
+
+    # check if havnig an extra rule with coordinates then they are not copy pasted too
+    assert len(result_dataset.output.coords) == 1
+
+
 def test_execute_rule_throws_error_for_unknown_input_variable():
     """Tests that trying to execute a rule with an unknown input variable
     throws an error, and the error message."""