curl https://financialmodelingprep.com/api/v3/historicals/sp500_constituent?apikey=YOUR_API_KEY
[
{
"dateAdded" : "July 21, 2021",
"addedSecurity" : "",
"removedTicker" : "ALXN",
"removedSecurity" : "Alexion Pharmaceuticals",
"date" : "2021-07-21",
"reason" : "AstraZeneca Plc acquired Alexion Pharmaceuticals.",
"symbol" : "ALXN"
}, {
"dateAdded" : "July 21, 2021",
"addedSecurity" : "Moderna",
"removedTicker" : "",
"removedSecurity" : "",
"date" : "2021-07-21",
"reason" : "AstraZeneca Plc acquired Alexion Pharmaceuticals.",
"symbol" : "MRNA"
}, {
"dateAdded" : "June 4, 2021",
"addedSecurity" : "",
"removedTicker" : "HFC",
"removedSecurity" : "HollyFrontier",
"date" : "2021-06-04",
"reason" : "Market capitalization change.",
"symbol" : "HFC"
}, ...
]