import pandas

# создаём усовершенствованную таблицу
def addData(df: pandas.DataFrame):

    # узнаём средние значения для всех столбцов
    mean_store_sales = df['Store_Sales'].mean()
    mean_daily_customer_count = df['Daily_Customer_Count'].mean()
    mean_items_available = df['Items_Available'].mean()
    mean_store_area = df['Store_Area'].mean()

    additionForTable = int(len(df) / 10)

    # добавили 10% значений
    for i in range(additionForTable):
        df.loc[len(df.index)] = [mean_store_area, mean_items_available, mean_daily_customer_count, mean_store_sales]

    return df