THETA

Summary

Theta is one of the 'Greeks' in options trading that measures how much an option's price decreases as time passes, assuming all other factors remain constant. Think of it as the 'time tax' on options - every day that passes, an option loses some value simply because it has less time to potentially become profitable. Theta is typically expressed as a negative number (like -0.05) indicating how much dollar value the option loses per day. This time decay accelerates as the option approaches its expiration date, making theta particularly important for options traders who need to understand how time affects their positions.

Usage Context

Understanding theta is crucial when learning about options pricing models, risk management strategies, and making decisions about when to buy or sell options. It's particularly important for understanding why holding options positions can be costly over time.

Common Confusions

• Thinking theta affects intrinsic value (it only affects time value)
• Believing theta decay is constant over time (it accelerates near expiration)
• Confusing theta with other Greeks like delta
• Not understanding that theta can be positive for short option positions
• Assuming weekend days don't contribute to time decay