diff --git a/src/spi/binary/__init__.py b/src/spi/binary/__init__.py
index 938efe9..29674f1 100644
--- a/src/spi/binary/__init__.py
+++ b/src/spi/binary/__init__.py
@@ -776,7 +776,7 @@ def build_schedule(schedule):
             child = build_name(name)
             programme_element.children.append(child)
        # descriptions
-       for description in programme.descriptions:
+        for description in programme.descriptions:
             child = build_description(description)
             programme_element.children.append(child)
         # locations