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If NYSE has market makers, what is the role of NYSE ARCA which is an ECN
Electronic trading is many orders of magnitude cheaper and more liquid than floor trading and is rapidly displacing it. Stil, electronic trading accounts for 79% of stock trading volume in the U.S. Polcari is losing the battle. Floor trading is still offered, but it's only used for bulk orders, so electronic trading is servicing small trades at minimum prices while floor trading is now the concierge service.