The current value of AMEX Composite Index is 4778.20 USD — it has fallen by 1.06% in the past 24 hours.
AMEX Composite Index value has decreased by 5.87% in the past week, since last month it has shown a 0.32% increase, and over the year it's increased by 10.80%.
AMEX Composite Index is just a number that lets you track performance of the instruments comprising the index, so you can't invest in it directly. But you can buy AMEX Composite Index futures or funds or invest in its components.