diff --git a/spread_backtest.py b/spread_backtest.py
index 3b700c1..86aaaa4 100644
--- a/spread_backtest.py
+++ b/spread_backtest.py
@@ -20,6 +20,8 @@ class Spread_Backtest():
         start: str, 
         end: str
     ):
+        # 更新可回测时间
+        self.trader.update_avaliable_date()
         # 确定回测的开始和结束时间
         if len(self.trader.account_history) > 0:
             bkt_start = max(start, self.trader.avaliable_date.index.min(), self.trader.account_history['date'].max())
diff --git a/trader.py b/trader.py
index 7c88c6b..8f580cf 100644
--- a/trader.py
+++ b/trader.py
@@ -190,6 +190,13 @@ class Trader(Account):
         else:
             self.today_data['close'] = DataLoader(self.today_data['basic'].data[['close_post']].rename(columns={'close_post':'price'}))
     
+    def update_avaliable_date(self):
+        """
+        更新可执行日期
+        """
+        # 可执行日期
+        self.avaliable_date = pd.Series(index=[f.split('.')[0] for f in os.listdir(self.data_root['basic'])]).sort_index()
+    
     def get_weight(self, date, total_weight, next_position):
         """
         计算个股仓位