SPDR S&P 500 ETF Trust SPY

The route row on Robinhood Chain and the other issuers the book reads, for reference, normalised to one unit and set against one reference price.

Book: unread

Tracked here

Reference price

Chainlink Robinhood SPY / USD on Robinhood Chain.

Feed 0x319724394D3A0e3669269846abE664Cd621f9f6A

The reference carries its own state and age. Against an unread reference the book shows no spread. How states work