A system and method is provided to enable traders to price improve on an item at an amount less than a predetermined pricing increment. Traders can improve on the price of the item using different price improvement levels (e.g., four different levels). The price improvement according to the invention is a dynamic price improvement, which enables a dynamic order to maintain a predetermined position in a trading stack relative to other orders in the stack. The dynamic order may maintain its position in the trading stack by adjusting (e.g., increasing or decreasing) its price improvement level depending on market conditions. For example, a dynamic order may increases its price improvement level such that it stays at least one level ahead of the next best order in the trading stack. If the level cannot be further increased, the dynamic order may use its timestamp to maintain its position in the stack.