diff --git a/cloudkitty/collector/ceilometer.py b/cloudkitty/collector/ceilometer.py
index 5303c385..fa036d85 100644
--- a/cloudkitty/collector/ceilometer.py
+++ b/cloudkitty/collector/ceilometer.py
@@ -15,9 +15,12 @@
 #
 # @author: Stéphane Albert
 #
+import decimal
+
 from ceilometerclient import client as cclient
 from keystoneauth1 import loading as ks_loading
 from oslo_config import cfg
+from oslo_utils import units
 
 from cloudkitty import collector
 from cloudkitty import utils as ck_utils
@@ -198,7 +201,7 @@ class CeilometerCollector(collector.BaseCollector):
                                                  image)
             image = self._cacher.get_resource_detail('image',
                                                      image_id)
-            image_size_mb = image_stats.max / 1048576.0
+            image_size_mb = decimal.Decimal(image_stats.max) / units.Mi
             image_data.append(self.t_cloudkitty.format_item(image,
                                                             'MB',
                                                             image_size_mb))
@@ -262,7 +265,7 @@ class CeilometerCollector(collector.BaseCollector):
                                                  tap)
             tap = self._cacher.get_resource_detail('network.tap',
                                                    tap_id)
-            tap_bw_mb = tap_stat.max / 1000000.0
+            tap_bw_mb = decimal.Decimal(tap_stat.max) / units.M
             bw_data.append(self.t_cloudkitty.format_item(tap,
                                                          'MB',
                                                          tap_bw_mb))
diff --git a/cloudkitty/collector/gnocchi.py b/cloudkitty/collector/gnocchi.py
index 663ed675..f54868c1 100644
--- a/cloudkitty/collector/gnocchi.py
+++ b/cloudkitty/collector/gnocchi.py
@@ -18,6 +18,7 @@ import decimal
 from gnocchiclient import client as gclient
 from keystoneauth1 import loading as ks_loading
 from oslo_config import cfg
+from oslo_utils import units
 
 from cloudkitty import collector
 
@@ -279,9 +280,11 @@ class GnocchiCollector(collector.BaseCollector):
             resource_data.pop('metrics', None)
             # Convert network.bw.in, network.bw.out and image unit to MB
             if resource.get('type') == 'instance_network_interface':
-                resource_data[qty] = resource_data[qty] / 1000000.0
+                resource_data[qty] = (
+                    decimal.Decimal(resource_data[qty]) / units.M)
             elif resource.get('type') == 'image':
-                resource_data[qty] = resource_data[qty] / 1048576.0
+                resource_data[qty] = (
+                    decimal.Decimal(resource_data[qty]) / units.Mi)
             data = self.t_cloudkitty.format_item(
                 resource_data,
                 unit,