>>> s.str.count('\\$')
        0    1
        1    0
        2    1
        3    2
        4    2
        5    0
        dtype: int64

        This is also available on Index

        >>> pd.Index(['A', 'A', 'Aaba', 'cat']).str.count('a')
        Int64Index([0, 0, 2, 1], dtype='int64')
        Frk