When did the New York Stock Exchange relaunch the Composite Index?

Can you tell me when exactly the New York Stock Exchange decided to relaunch their Composite Index? Was there a specific event or period of time that triggered this decision? I'm curious to know the historical context behind this relaunch and how it may have impacted the financial markets and investors. I'm also interested in understanding the significance of the Composite Index in the overall landscape of stock market indices.