diff --git a/freqtrade/ft_types/backtest_result_type.py b/freqtrade/ft_types/backtest_result_type.py
index 27cdb6126..4cd8f2a58 100644
--- a/freqtrade/ft_types/backtest_result_type.py
+++ b/freqtrade/ft_types/backtest_result_type.py
@@ -1,3 +1,4 @@
+from copy import deepcopy
 from typing import Any
 
 from typing_extensions import TypedDict
@@ -15,11 +16,13 @@ class BacktestResultType(TypedDict):
 
 
 def get_BacktestResultType_default() -> BacktestResultType:
-    return {
-        "metadata": {},
-        "strategy": {},
-        "strategy_comparison": [],
-    }
+    return deepcopy(
+        {
+            "metadata": {},
+            "strategy": {},
+            "strategy_comparison": [],
+        }
+    )
 
 
 class BacktestHistoryEntryType(BacktestMetadataType):
diff --git a/freqtrade/optimize/optimize_reports/optimize_reports.py b/freqtrade/optimize/optimize_reports/optimize_reports.py
index c0188673a..e5b526779 100644
--- a/freqtrade/optimize/optimize_reports/optimize_reports.py
+++ b/freqtrade/optimize/optimize_reports/optimize_reports.py
@@ -18,7 +18,7 @@ from freqtrade.data.metrics import (
     calculate_sortino,
     calculate_sqn,
 )
-from freqtrade.ft_types import BacktestResultType
+from freqtrade.ft_types import BacktestResultType, get_BacktestResultType_default
 from freqtrade.util import decimals_per_coin, fmt_coin, get_dry_run_wallet
 
 
@@ -587,11 +587,7 @@ def generate_backtest_stats(
     :param max_date: Backtest end date
     :return: Dictionary containing results per strategy and a strategy summary.
     """
-    result: BacktestResultType = {
-        "metadata": {},
-        "strategy": {},
-        "strategy_comparison": [],
-    }
+    result: BacktestResultType = get_BacktestResultType_default()
     market_change = calculate_market_change(btdata, "close")
     metadata = {}
     pairlist = list(btdata.keys())