NYA.X is the ticker symbol for the NYSE Composite Index. It represents the performance of all the common stocks listed on the New York Stock Exchange (NYSE), including foreign stocks, American Depositary Receipts (ADRs), and Real Estate Investment Trusts (REITs). The NYSE Composite Index is a broad-based market index that includes more than 1,900 stocks, making it a good barometer of the overall health of the US stock market.