How it works
Under itayose, all outstanding buy and sell orders received up to that point are aggregated, a single price at which supply and demand balance is calculated, and orders meeting that price are then matched and executed all at once. This method is used to determine the opening and closing prices, and is also used when trading resumes after a halt.
Difference from zaraba
During zaraba, orders are matched and executed one by one, based on price priority and time priority, as they arrive. Itayose differs in that orders are collected over a period of time and then matched all at once. Note that if supply and demand become significantly imbalanced during zaraba, the quote may be updated as a special quote, after which the price may be determined using a method similar to itayose.