On a trading desk, the volume you executed for a client divided by the client's total volume in that product, where the total can be estimated. Hit ratio counts requests; flow share counts size.
Flow share = notional won ÷ client's total notional in the product
The total comes from venue data, a benchmark provider or the client's own disclosure, with the source recorded. Where no total is reliable, report hit ratio alone.
A high hit ratio on a small flow share means the client sends only the trades it intends to do with you. A low hit ratio on a large request count means you are the price check. The pair says which.
Volume executed for a client divided by the client's total volume in the product, estimated from venue data or the client's own figures, with the source stated.
A client traded about $2.0 billion in the product in the quarter. The desk executed $140 million: 7 percent. Its hit ratio on what it was shown was 35 percent, so the problem is not being shown the flow.
Hit ratio read without flow share. A desk can win a third of what it sees and see very little.