Why does newly-formed dict only consist of last row of each year?

[Mark17]

Hi all,

I'm trying to convert two columns ('BIRTH_YEAR', 'NAME') of baby_names into a dictionary. Why does the newly-formed dictionary only consist of the last df row of each year?

baby_name_dict = {}
print(baby_names.info(), '\n')
baby_name_dict = dict(zip(baby_names.BIRTH_YEAR, baby_names.NAME))
print(f'baby_name_dict is:  {baby_name_dict}.')

Output:
<class 'pandas.core.frame.DataFrame'>
RangeIndex: 13962 entries, 0 to 13961
Data columns (total 6 columns):
 #   Column      Non-Null Count  Dtype 
---  ------      --------------  ----- 
 0   BIRTH_YEAR  13962 non-null  int64 
 1   GENDER      13962 non-null  object
 2   ETHNICTY    13962 non-null  object
 3   NAME        13962 non-null  object
 4   COUNT       13962 non-null  int64 
 5   RANK        13962 non-null  int64 
dtypes: int64(3), object(3)
memory usage: 654.6+ KB
None 

baby_name_dict is:  {2011: 'ZEV', 2012: 'ZEV', 2013: 'Zev', 2014: 'Zev'}.

Getting myself ready for a really foolish oversight... :)