diff --git a/doorcontrol/views.py b/doorcontrol/views.py
index 80121f8..bedacc0 100644
--- a/doorcontrol/views.py
+++ b/doorcontrol/views.py
@@ -5,7 +5,7 @@ from django.contrib.auth.mixins import PermissionRequiredMixin
 from django.contrib.postgres.aggregates import StringAgg
 from django.core.exceptions import BadRequest
 from django.db.models import Count, F, FloatField, Func, Q, Value, Window
-from django.db.models.functions import Lead, Trunc
+from django.db.models.functions import Lead, NullIf, Trunc
 from django.urls import path, reverse_lazy
 from django.utils.text import slugify
 from django.views.generic.list import ListView
@@ -173,7 +173,7 @@ class AccessPerUnitTime(BaseAccessReport):
                 members_delta=(
                     F("members")
                     / Window(
-                        Lead("members"),
+                        Lead(NullIf("members", 0.0)),
                         order_by="-unit_time",
                         output_field=FloatField(),
                     )
@@ -184,7 +184,7 @@ class AccessPerUnitTime(BaseAccessReport):
                 access_count_delta=(
                     F("access_count")
                     / Window(
-                        Lead("access_count"),
+                        Lead(NullIf("access_count", 0.0)),
                         order_by="-unit_time",
                         output_field=FloatField(),
                     )