diff --git a/nummi/history/utils.py b/nummi/history/utils.py
index 3606959..c61fc88 100644
--- a/nummi/history/utils.py
+++ b/nummi/history/utils.py
@@ -1,6 +1,6 @@
 import datetime
 
-from django.db.models import Avg, Q, StdDev, Sum
+from django.db.models import Q, Sum
 from django.db.models.functions import Abs, TruncMonth
 
 
@@ -36,12 +36,16 @@ def history(transaction_set):
     return {
         "data": _data,
         "max": {
-            "pm": max(
-                _history.aggregate(
-                    max=Avg("sum_p", default=0) + StdDev("sum_p", default=0),
-                    min=Avg("sum_m", default=0) - StdDev("sum_m", default=0),
-                ).values(),
-            ),
-            "sum": _history.aggregate(max=Avg(Abs("sum")) + StdDev(Abs("sum")))["max"],
+            "pm": 125
+            * max(
+                _history.order_by("-sum_p")[len(_history) // 10]["sum_p"],
+                _history.order_by("-sum_m")[len(_history) // 10]["sum_m"],
+            )
+            / 100,
+            "sum": 125
+            * _history.annotate(abs_sum=Abs("sum")).order_by("-abs_sum")[
+                len(_history) // 10
+            ]["abs_sum"]
+            / 100,
         },
     }