While it is impractical to attempt listing ratio spreads that would provide strict neutrality or parity based on the prevailing exchange rate at any given moment, the following workaround might provide reasonable approximation.

Starting September 14, 2026, we will provide implied spread order books for the following ratios concurrently:

^{Source: CME Group}

The above table shows the five concurrent spread order books for Nikkei (USD)-Nikkei (JPY) spreads. For example, when a buy order is entered in the 4:7 spread, the trading matching algorithm will attempt to match the order to sell orders of the 4:7 spread, as well as a combination of sell orders for Nikkei (USD) futures (NKD) and buy orders for Nikkei (JPY) futures (NIY). At an exchange rate of 175 yen per USD, this ratio will achieve neutrality. As the exchange rate evolves over time, market participants will be able to enter spread orders at a ratio closer to the prevailing exchange rate to achieve parity. In addition, since all five spread ratios are available concurrently, market participants may use a combination of 2:3 and 4:7 to target an exchange rate of 160, for example.

To promote liquidity of the spread order book around the current exchange rate, the match engine will prioritize trade matching at the ratio closest to what the prevailing exchange rate^[1] implies in the event resting orders of more than one spread ratio can be matched to incoming orders.

Note that ratio spreads will only be available for spreads of Nikkei (USD) and Nikkei (JPY) contracts with identical expirations.

Order quantity: When entering an order for a ratio spread, note that the total number of contracts traded is the spread quantity multiplied by the leg quantity per spread. For example, buying five spreads of the 4:7 ratio spread means buying 20 NKD futures (5 x 4) and selling 35 NIY futures (5 x 7) when fully executed.

Order price: The ratio spread order price is the (average) price of the NKD futures less the average price of the NIY futures. For example, buying one 4:7 spread at the price of 15 means that the participant is buying the spread with the average price of the four contracts of Nikkei (USD) no higher than 15 points over the average price of the seven contracts of Nikkei (JPY) futures in the trade execution.

If there is a spread order selling the same 4:7 spread at the price of 15, the spread orders will be able to be matched against each other. The NIY futures leg price will be set at the most recent price^[2] of the NIY contract. It serves as the anchor for pricing the NKD futures leg, which will be set to 15 above the NIY futures leg price. 

Alternatively, if there is no matchable spread order against the incoming spread order, the match algorithm will then look at the order books of NIY and NKD futures and determine if the best offers of NKD futures and best bids of NIY futures at the stated ratio can be matched. If the implied spreads from the outright order books are matched to the spread order, the leg prices will therefore be the prices for each of the outright orders matched to the spread order.

Note that it is possible the four contracts of NKD futures have different prices and the seven contracts of NIY futures can have different prices as well. As long as the average of the NKD futures prices minus average of the NIY futures prices is at or below the ratio spread bid price of 15, the orders will match and leg prices printed accordingly. Precisely because of this implied matching possibility, the following scenarios and considerations are warranted.

1. The price improvement will be granted to the ratio spread order only – both NIY and NKD futures outright orders will need to abide by their respective tradeable tick size of 5 index points. As such, the price improvement will accrue to the ratio spread order.
2. Since both NIY and NKD futures ticks in 5 index points, ratio spread orders will be allowed to enter in price increments of 1 index point. For example, in the 4:7 spread, even if just one of the seven NIY contracts is at one tick lower while there are six contracts at the best bid, the implied spread price will be 5/7 index points higher. Allowing ratio spread orders to be entered at 1 index point increments will allow for safer order entry than the normal 5-point increment affords^[3]  (i.e., better control on the entire 4:7 spread package).
3. Implied in orders will be displayed. The ratio spread order book will display the implied in orders from the outright order book (i.e., what the spread matching algo can achieve from legging in the orders from the outright books). Note that the displayed implied in orders will also be rounded to the next 1 index point increment for display purposes, hence the possible price improvement to the incoming ratio spread orders.
4. Implied out orders will not be displayed. While an incoming outright order can possibly be matched to a combination of resting orders in the ratio order book and in the other outright order book, these implied outs will not be displayed in the outright order book, since there will be a quantity requirement for the three-way trade to occur.
5. Please also note that while it is logically possible to match spread orders of two distinct ratios and an outright order (e.g., a buy order of 4:7), a sell order of 4:5 and a buy order of NIY contract at a quantity of two, if the prices lined up, this type of three-way implied spread matching will not be matched by the trade matching algo.

To summarize, non-1:1 ratio orders can be entered at 1 index point increments and can see price improvements in the actual trade when matched to outright orders. The non-1:1 ratio spread books will also be displayed in the same 1 increments. The 1:1 spreads will remain unchanged at the 5-point increments. The display properties of the implieds associated with 1:1 spreads will remain unchanged as well. 

This improved implied ratio spreading capability should prove to be beneficial to the Nikkei 225 futures market.

1.  Note that the priority is reset periodically (every quarter) based on the prevailing exchange rate.
2. CLAST in the NIY outright market will be the anchor leg price.
3. If the ratio spread orders can only enter at an increment of 5, there is a bigger leg risk – one might be willing to pay slightly above, say, 15.00. Indeed, the implied is showing 16 (meaning it is just over 15). But entering a price of 20.00 is much riskier. The market participant will be committed to buying the entire spread up to 20.00, 4 points higher than intended for the entire package.