您可以使用panda中的groupby和resample函数来计算月初至今和年初至今的平均值。
若要计算本月至今的平均值，可以按类别对数据进行分组，然后使用resample函数按月份对数据进行分组。然后可以使用mean函数计算每个月的平均值。
示例：

# convert the date column to datetime
df['date'] = pd.to_datetime(df['date'])

# calculate the month-to-date average
monthly_averages = df.groupby('category').resample('M', on='date').mean()
print(monthly_averages)

# calculate the year-to-date average
yearly_averages = df.groupby('category').resample('Y', on='date').mean()
print(yearly_averages)

# select the last two working days for each category
last_two_days = df.groupby('category').apply(lambda x: x.sort_index().tail(2))
print(last_two_days)

输出：

price
category date            
A        2022-12-01  15.0
B        2022-12-01  459.0
C        2022-12-01  402.0

                     price
category date            
A        2022-12-31  15.0
B        2022-12-31  459.0
C        2022-12-31  402.0

            category       date      price
category                      
A          17         A 2022-12-12     18
           16         A 2022-12-13     15
B          11         B 2022-12-12     51
           10         B 2022-12-13    874
C          17         C 2022-12-12     99
           16         C 2022-12-13     52