It can be constructed by subscription contract or put contract.
The construction method of bull market call option spread strategy: buy a call option with lower exercise price and sell a call option with the same expiration date and higher exercise price.
Construction cost: call option premium with lower exercise price-call option premium with higher exercise price Maximum loss due date: construction cost.
Maximum profit on maturity date: higher exercise price-lower exercise price-construction cost.
Break-even point: the underlying share price = lower exercise price+construction cost.
The construction method of bull market put spread strategy: buy a put option with lower exercise price and sell a put option with higher limit price in the same period.
Construction income: put option premium with higher exercise price-put option premium with lower exercise price.
Maximum loss on maturity date: higher exercise price-lower exercise price-construction income.
Maximum benefits on maturity date: construction benefits.
Break-even point: the underlying share price = higher exercise price-construction income.
For the bull market spread strategy, the maturity profit and loss curve is the same whether the subscription contract or the put contract is adopted, and the difference lies in the difference between the net premium (put) or the net premium (subscription) when the position is opened.