diff --git a/google/cloud/bigtable/data/_metrics/data_model.py b/google/cloud/bigtable/data/_metrics/data_model.py
index 4699ef20f..2d249621c 100644
--- a/google/cloud/bigtable/data/_metrics/data_model.py
+++ b/google/cloud/bigtable/data/_metrics/data_model.py
@@ -15,9 +15,7 @@
 
 from typing import Callable, Any, Generator, Tuple, cast, TYPE_CHECKING
 
-import datetime
 import time
-import os
 import re
 import logging
 
@@ -105,7 +103,7 @@ class CompletedOperationMetric:
     cluster_id: str
     zone: str
     is_streaming: bool
-    flow_throttling_time_ns: int = 0.0
+    flow_throttling_time_ns: int = 0
 
 
 @dataclass
diff --git a/tests/unit/data/_metrics/test_data_model.py b/tests/unit/data/_metrics/test_data_model.py
index 987ef8582..c79546f1c 100644
--- a/tests/unit/data/_metrics/test_data_model.py
+++ b/tests/unit/data/_metrics/test_data_model.py
@@ -15,7 +15,6 @@
 import time
 import pytest
 import mock
-import datetime
 
 from google.cloud.bigtable.data._metrics.data_model import OperationState as State
 from google.cloud.bigtable_v2.types import ResponseParams