Patent ID: 8533098

Claim:
A trading system comprising: a database, said database containing data related to a pair of investment items; said database containing a plurality of bid data and ask data on each said investment item over a given period, and a plurality of ratio indicators on the bid/ask spread between said pair of investment items; and a processor determining a valuation of said pair of investment items in relation to each other, wherein a given ratio indicator is based upon respective correlated bid and ask data on said pair of investment items, said correlated bid and ask data containing bid one and ask one for the first investment item, and bid two and ask two for said second of said pair of investment items, and wherein a pair of ratio indicators are computed, a first said ratio indicator being computed by dividing bid one by ask two, and a second ratio indicator being computed by dividing ask one by bid two, whereby a plurality of said ratio indicators provide improved arbitrage and other investment opportunities.