diff --git a/distro/README b/distro/README
index ed2b585..f84d4a0 100644
--- a/distro/README
+++ b/distro/README
@@ -21,11 +21,13 @@ Authors
 --------------------------------------------------
  
 * Luca Frosini (luca.frosini-AT-isti.cnr.it), Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo" - CNR, Pisa (Italy).
+* Alessandro Pieve (alessandro.pieve-AT-isti.cnr.it), Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo" - CNR, Pisa (Italy).
 
 Maintainers
 -----------
  
 * Luca Frosini (luca.frosini-AT-isti.cnr.it), Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo" - CNR, Pisa (Italy).
+* Alessandro Pieve (alessandro.pieve-AT-isti.cnr.it), Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo" - CNR, Pisa (Italy).
  
  
 Download information
diff --git a/distro/changelog.xml b/distro/changelog.xml
index dbbfff1..0a34213 100644
--- a/distro/changelog.xml
+++ b/distro/changelog.xml
@@ -1,11 +1,14 @@
 <ReleaseNotes>
-	<Changeset component="org.gcube.accounting.accounting-analytics.2-0-0" date="${buildDate}">
-		<Change>Reoganized API and added new API to get top values #2253</Change>
+	<Changeset component="org.gcube.accounting.accounting-analytics.2-1-0" date="${buildDate}">
+		<Change>Added getUsageValue() API</Change>
 	</Changeset>
-   <Changeset component="org.gcube.accounting.accounting-analytics.1-2-0" date="2015-04-08">
+	<Changeset component="org.gcube.accounting.accounting-analytics.2-0-0" date="2016-05-18">
+		<Change>Reorganized API and added new API to get top values #2253</Change>
+	</Changeset>
+   <Changeset component="org.gcube.accounting.accounting-analytics.1-2-0" date="2016-04-08">
 		<Change>Ready for ScopeProvider Removal #2194</Change>
 	</Changeset>
-   <Changeset component="org.gcube.accounting.accounting-analytics.1-1-0" date="2015-02-08">
+   <Changeset component="org.gcube.accounting.accounting-analytics.1-1-0" date="2016-02-08">
 		<Change>Internal Changes due to Accounting Lib generalization #1746</Change>
 	</Changeset>
 	<Changeset component="org.gcube.accounting.accounting-analytics.1-0-0" date="2015-12-09">
diff --git a/src/main/java/org/gcube/accounting/analytics/persistence/AccountingPersistenceBackendQuery.java b/src/main/java/org/gcube/accounting/analytics/persistence/AccountingPersistenceBackendQuery.java
index f9778ea..d20096b 100644
--- a/src/main/java/org/gcube/accounting/analytics/persistence/AccountingPersistenceBackendQuery.java
+++ b/src/main/java/org/gcube/accounting/analytics/persistence/AccountingPersistenceBackendQuery.java
@@ -5,7 +5,6 @@ package org.gcube.accounting.analytics.persistence;
 
 import java.util.Calendar;
 import java.util.List;
-import java.util.Map;
 import java.util.SortedMap;
 import java.util.SortedSet;