diff --git a/ogn/collect/database.py b/ogn/collect/database.py
index b62ddff..3d193cb 100644
--- a/ogn/collect/database.py
+++ b/ogn/collect/database.py
@@ -30,7 +30,7 @@ def import_ddb():
 
     logger.info("Import registered devices fom the DDB...")
     counter = update_devices(app.session, AddressOrigin.ogn_ddb, get_ddb())
-    logger.info("Imported %i devices." % counter)
+    logger.info("Imported {} devices.".format(counter))
 
 
 @app.task
@@ -39,7 +39,7 @@ def import_file(path='tests/custom_ddb.txt'):
 
     logger.info("Import registered devices from '{}'...".format(path))
     counter = update_devices(app.session, AddressOrigin.user_defined, get_ddb(path))
-    logger.info("Imported %i devices." % counter)
+    logger.info("Imported {} devices.".format(counter))
 
 
 @app.task
diff --git a/ogn/collect/logbook.py b/ogn/collect/logbook.py
index aa0834d..a748821 100644
--- a/ogn/collect/logbook.py
+++ b/ogn/collect/logbook.py
@@ -86,6 +86,6 @@ def compute_takeoff_and_landing():
     result = app.session.execute(ins)
     counter = result.rowcount
     app.session.commit()
-    logger.debug("New/recalculated takeoffs and landings: %s" % counter)
+    logger.debug("New/recalculated takeoffs and landings: {}".format(counter))
 
     return counter
diff --git a/ogn/commands/logbook.py b/ogn/commands/logbook.py
index 3e76a39..2bda31c 100644
--- a/ogn/commands/logbook.py
+++ b/ogn/commands/logbook.py
@@ -21,7 +21,7 @@ def compute():
     print("Compute takeoffs and landings...")
     result = compute_takeoff_and_landing.delay()
     counter = result.get()
-    print("New/recalculated takeoffs/landings: %s" % counter)
+    print("New/recalculated takeoffs/landings: {}"format(counter))
 
 
 @manager.command
diff --git a/ogn/utils.py b/ogn/utils.py
index fa4a0e5..c66ca08 100644
--- a/ogn/utils.py
+++ b/ogn/utils.py
@@ -49,15 +49,15 @@ def get_trackable(ddb):
     l = []
     for i in ddb:
         if i.tracked and i.address_type in address_prefixes:
-            l.append('{}{}'.format(address_prefixes[i.address_type], i.address))
+            l.append("{}{}".format(address_prefixes[i.address_type], i.address))
     return l
 
 
 def get_country_code(latitude, longitude):
     geolocator = Nominatim()
     try:
-        location = geolocator.reverse("%f, %f" % (latitude, longitude))
-        country_code = location.raw["address"]["country_code"]
+        location = geolocator.reverse("{}, {}".format(latitude, longitude))
+        country_code = location.raw['address']['country_code']
     except KeyError:
         country_code = None
     except GeopyError: