diff --git a/app/performance_platform/total_sent_notifications.py b/app/performance_platform/total_sent_notifications.py
index 62b38e390..1de291067 100644
--- a/app/performance_platform/total_sent_notifications.py
+++ b/app/performance_platform/total_sent_notifications.py
@@ -4,6 +4,7 @@ from app.dao.fact_notification_status_dao import (
 )
 
 
+# TODO: is this obsolete? it doesn't seem to be used anywhere
 def send_total_notifications_sent_for_day_stats(start_time, notification_type, count):
     payload = performance_platform_client.format_payload(
         dataset='notifications',
@@ -16,13 +17,12 @@ def send_total_notifications_sent_for_day_stats(start_time, notification_type, c
     performance_platform_client.send_stats_to_performance_platform(payload)
 
 
+# TODO: is this obsolete? it doesn't seem to be used anywhere
 def get_total_sent_notifications_for_day(day):
     email_count = get_total_sent_notifications_for_day_and_type(day, 'email')
     sms_count = get_total_sent_notifications_for_day_and_type(day, 'sms')
-    letter_count = get_total_sent_notifications_for_day_and_type(day, 'letter')
 
     return {
         "email": email_count,
         "sms": sms_count,
-        "letter": letter_count,
     }