List of S&P 500 historical constituents from 1996/01/02 to present. CSV format where each date contains a list of the constituents.
'sp500_constituents.csv' current S&P 500 composition from Wikipedia and output from 'sp500.py'
'sp_500_historical_components.csv' contains historical S&P 500 index membership from 1996 til present. Output from 'sp500.py'