diff --git a/web_app/__init__.py b/web_app/__init__.py
index 9fd6a17..00c1084 100644
--- a/web_app/__init__.py
+++ b/web_app/__init__.py
@@ -3,7 +3,7 @@
 from flask_bootstrap import Bootstrap
 from config import TEST_PATH
 from report import build_vertical_bar, build_lines_chart
-from storage_api import create_storage, Measurement
+from storage_api import Measurement
 from logging import getLogger, INFO
 
 import json
@@ -157,7 +157,10 @@
     d = {}
 
     for pair in b2.items():
-        b1[pair[0]] = pair[1]
+        if pair[0] in b1 and type(pair[1]) is list:
+            b1[pair[0]].extend(pair[1])
+        else:
+            b1[pair[0]] = pair[1]
 
 
 @app.route("/", methods=['GET', 'POST'])