Trading Time
Contract trading is on a 7*24-hour round-the-clock trading unless it is in a settlement or delivery between 16:00 to 16:30 (UTC+8) everyday.

Trading Types
Trading types can be divided into open and close. Each type can be further divided into two directions, long and short:

Open long means that users buy a certain number of contracts when the index is bullish. When the transaction is concluded, long positions will increase.

Close long means that users exit the market by offsetting the buying contracts held currently when the index is not bullish. When the transaction is concluded, long positions will decrease.

Open short means that users sell a certain number of contracts when the index is bearish. When the transaction is concluded, short positions will increase.

Close short means that users exit the market by offsetting the selling contracts held currently when the index is not bearish. When the transaction is concluded, short positions will decrease.

Order Types
Limit Order: Limit order must be filled at or below the limit price when users buy. Limit Order must be filled at or above the limit price when users sell.

Market Order: Market order does not limit price, and it must be filled at market price. Market order can only be filled with limit order.

Contract Unit
Cont

Continuous Auction
All trades except settlement and delivery are continuous auction. Continuou auction are filled according to the principle of price priority and time priority. When buying price is larger than or equal to selling price, the transaction is filled automatically. The fill price is equal to one of the three prices which in the middle: the buying price (bp), the selling price (sp) and the last price (lp).

Which means:
When bp≧sp≧lp, the fill price = sp
When bp≧lp≧sp, the fill rice = lp
When lp≧bp≧sp, the fill price = bp

Position merge
After order fills, positions in the same type and the same direction of a contract will be merged. One contract account can only have 6 positions at most, which are long/short positions in two near-term weekly contracts, long/short positions in one quarterly contract.

For the same type of contract, positions will be merged. If user first goes long a 1 BTC weekly contract, and then goes long a 2 BTC weekly contract, then he will own a 3 BTC weekly contract displayed at the positions. These contracts will not be separated.

When a position is closed, the cost will be calculated by the moving average method. That means it will calculate gains with the average open price of all positions instead of distinguishing open price of each position.

Average Open Price = (Number of Fill Price 1 + Number of Fill Price 2 +...)/ (Number of Fill Price 1 / Fill Price 1 + Number of Fill Price 2/ Fill Price 2 +...)

For example, a user opens a BTC week contract for 1000 USD and two BTC week contracts for 1500 USD / BTC (the face value of the contract is 100 USD), average opening price of the user is 100 * (1 + 2) / (100 / 100 + 200 / 1500) = 1285.7 USD.