ثيتا الخيارات هو مقياس يستخدم في علم خيارات التداول، ويشير إلى معدل تغير سعر الخيار مع مرور الوقت. يمثل الثيتا مقدار المال الذي يُفترض أن ينخفض به السعر الناتج عن الخيار (قيمة الخيار) يومياً نتيجة لتأثير الزمن، بينما تقترب تاريخ انتهاء الصلاحية. بشكل عام، كلما اقترب الخيار من انتهاء الصلاحية، زادت قيمة الثيتا، مما يعني أن القيمة الوقتية للخيار تتقلص. يتم استخدام الثيتا من قبل المتداولين لفهم تأثير الزمن على الخيارات التي يمتلكونها أو يخططون للتداول بها.

Definition and Examples of Theta

Theta is a measure of the rate of change of the value of options on a daily basis as the expiration date approaches. Simply put, the value of theta tells you the rate of time decay as the contract nears expiration. Investors use theta as a way to manage market risk when trading options because it helps them understand how time decay affects the price of an options contract.

How Theta Works

Since options lose value as the expiration date approaches, theta is usually expressed as a negative number. Therefore, if the value of theta is -0.40, the options contract is expected to decline by approximately $0.40 per day. Since options contracts generally give the investor the right to buy or sell 100 shares of the underlying asset, we can assume that a decrease of $0.40 per day would equate to a decline of $40 per day ($0.40 × 100 = $40).

Alternatives to Theta

Other alternatives to theta include analyzing options contracts using any of the other four Greek metrics: Delta, Gamma, Vega, and Rho. Delta: measures the change in the price of an options contract as the price of the underlying asset changes. Gamma: the rate of change that options will experience based on the change in the price of the underlying asset. Vega: measures the sensitivity of the price of an options contract to changes in implied volatility. Rho: measures the sensitivity of the option’s price to a change in interest rates.

What This Means for Individual Investors

Perhaps one of the most significant differences between investing in stocks and investing in options is the fact that options have an expiration date. Therefore, time is crucial and can significantly affect your profit or loss. Understanding theta for options means you can manage time decay for the option as it approaches its expiration date and adjust your strategies accordingly.

Key Takeaways

Theta is a measure of time decay. It assesses how much the value of the option decreases as the expiration date approaches. Theta, like other metrics referred to by Greek letters, is used to manage and evaluate some of the risks associated with options contracts. Theta is derived from the option based on the assumption of continuous changes in price and implied volatility of the underlying stocks. Thus, theta will vary from day to day. Theta is a theoretical measure that assumes continuous changes in price and implied volatility, meaning that the theta of an options contract may change from day to day. Understanding how to use theta as an investor will help you manage time decay for each options contract you purchase.

Source: https://www.thebalancemoney.com/what-is-theta-5204828