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Pandas allows users to add or subtract a number of months from a given date using the pandas.DateOffset object. This object can be used with the pandas.Series.dt.date or pandas.DataFrame.shift to add or subtract months from a given date. The DateOffset object can be used to add or subtract a number of months from a given date or from the current date. This is a useful tool for manipulating dates in data frames and can be used to quickly analyze data over different time periods.
You can use the following methods to add and subtract months from a date in pandas:
Method 1: Add Months to Date
from pandas.tseries.offsets import DateOffset
df['date_column'] + DateOffset(months=3)
Method 2: Subtract Months from Date
from pandas.tseries.offsets import DateOffset
df['date_column'] - DateOffset(months=3) The following examples show how to use each method in practice with the following pandas DataFrame:
import pandas as pd
#create DataFrame
df = pd.DataFrame({'date': pd.date_range(start='1/5/2022', freq='M', periods=10),
'sales': [6, 8, 9, 5, 4, 8, 8, 3, 5, 9]})
#view DataFrame
print(df)
date sales
0 2022-01-31 6
1 2022-02-28 8
2 2022-03-31 9
3 2022-04-30 5
4 2022-05-31 4
5 2022-06-30 8
6 2022-07-31 8
7 2022-08-31 3
8 2022-09-30 5
9 2022-10-31 9
Example 1: Add Months to Date in Pandas
The following code shows how to create a new column that adds 3 months to the value in the date column:
from pandas.tseries.offsets import DateOffset
#create new column that adds 3 months to date
df['date_plus3'] = df.date + DateOffset(months=3)
#view updated DataFrame
print(df)
date sales date_plus3
0 2022-01-31 6 2022-04-30
1 2022-02-28 8 2022-05-28
2 2022-03-31 9 2022-06-30
3 2022-04-30 5 2022-07-30
4 2022-05-31 4 2022-08-31
5 2022-06-30 8 2022-09-30
6 2022-07-31 8 2022-10-31
7 2022-08-31 3 2022-11-30
8 2022-09-30 5 2022-12-30
9 2022-10-31 9 2023-01-31 The new column date_plus3 represents the values in the date column with three months added to each value.
Example 2: Subtract Months from Date in Pandas
The following code shows how to create a new column that subtracts 3 months to the value in the date column:
from pandas.tseries.offsets import DateOffset
#create new column that subtracts 3 months from date
df['date_minus3'] = df.date + DateOffset(months=3)
#view updated DataFrame
print(df)
date sales date_minus3
0 2022-01-31 6 2021-10-31
1 2022-02-28 8 2021-11-28
2 2022-03-31 9 2021-12-31
3 2022-04-30 5 2022-01-30
4 2022-05-31 4 2022-02-28
5 2022-06-30 8 2022-03-30
6 2022-07-31 8 2022-04-30
7 2022-08-31 3 2022-05-31
8 2022-09-30 5 2022-06-30
9 2022-10-31 9 2022-07-31 The new column date_minus3 represents the values in the date column with three months subtracted from each value.