diff --git a/s3transfer/bandwidth.py b/s3transfer/bandwidth.py
index 3ac9b340..8b3f6f50 100644
--- a/s3transfer/bandwidth.py
+++ b/s3transfer/bandwidth.py
@@ -401,7 +401,14 @@ def record_consumption_rate(self, amt, time_at_consumption):
         self._last_time = time_at_consumption
 
     def _calculate_rate(self, amt, time_at_consumption):
-        return amt / (time_at_consumption - self._last_time)
+        time_delta = time_at_consumption - self._last_time
+        if time_delta <= 0:
+            # While it is really unlikley to see this in an actual transfer,
+            # we do not want to be returning back a negative rate or try to
+            # divide the amount by zero. So instead return back an infinite
+            # rate as the time delta is infinitesimally small.
+            return float('inf')
+        return amt / (time_delta)
 
     def _calculate_exponential_moving_average_rate(self, amt,
                                                    time_at_consumption):
diff --git a/tests/unit/test_bandwidth.py b/tests/unit/test_bandwidth.py
index c6bb1986..4f35a7a8 100644
--- a/tests/unit/test_bandwidth.py
+++ b/tests/unit/test_bandwidth.py
@@ -456,3 +456,10 @@ def test_get_projected_rate(self):
         self.assertEqual(projected_rate, 0.96)
         self.rate_tracker.record_consumption_rate(1, 3)
         self.assertEqual(self.rate_tracker.current_rate, projected_rate)
+
+    def test_get_projected_rate_for_same_timestamp(self):
+        self.rate_tracker.record_consumption_rate(1, 1)
+        self.assertEqual(
+            self.rate_tracker.get_projected_rate(1, 1),
+            float('inf')
+        )