Little is known about the joint dynamics of volume across the various contingent claims on the equity market. We study the time-series of trading activity in the cash S&P 500 index and its derivatives (options, the legacy and E-mini futures contracts, and the ETF), and consider their dynamic relation with the macroeconomy, over more than 3000 trading days during 1997–2009. Legacy futures volume has trended downward while other series have trended upward. Total futures volume has increased, suggesting that the trading in the legacy contract has been at least partially supplanted by trading in the E-mini contract. All series are highly cross-correlated and jointly dependent. Signed and absolute trading activity in contingent claims (most prominently, options) predicts shifts in aggregate state variables such as the short interest rate, and the term and credit spreads, as well as signed and absolute returns around major macroeconomic announcements. Overall, consistent with the informational role of options, their volume innovations have the strongest forecasting ability for fluctuations in the macroeconomic environment.