Understanding the Greeks

What are the Greeks?

The Greeks are mathematical values that describe how an option's price changes in response to various factors. For wheel traders, understanding the Greeks helps with strike selection, timing, and risk management.

The Four Main Greeks

Greek	Measures	Affected By
Delta	Price sensitivity	Stock movement
Theta	Time decay	Passage of time
Vega	Volatility sensitivity	IV changes
Gamma	Delta's rate of change	Stock movement

Delta: Directional Exposure

Delta measures how much an option's price changes when the stock moves $1.

For puts (always negative):

• Delta of -0.30 = option loses $0.30 when stock rises $1
• Also approximates probability of expiring ITM (~30%)

For calls (always positive):

• Delta of 0.30 = option gains $0.30 when stock rises $1
• Approximates probability of expiring ITM (~30%)

Wheel trading application:

• Use delta to select strike prices
• Target 0.20-0.30 delta for balanced risk/reward
• Lower delta = more conservative, less premium

Theta: Time is Money

Theta measures how much value an option loses each day due to time decay.

Example: Theta of -0.05 means the option loses $5 per day (per contract).

Key theta facts:

• Theta is always negative for option buyers
• Theta decay accelerates near expiration
• ATM options have the highest theta
• Deep ITM/OTM options have lower theta

Wheel trading application:

• Theta is your best friend as a seller
• Aim for 45-30 DTE to balance theta vs. gamma
• Track theta to understand daily P&L

Vega: Volatility Risk

Vega measures how much an option's price changes when implied volatility changes by 1%.

Example: Vega of 0.15 means a 1% increase in IV adds $15 to option value.

Key vega facts:

• High vega = sensitive to IV changes
• Longer-dated options have higher vega
• ATM options have highest vega

Wheel trading application:

• Sell options when IV is high (more premium)
• Close positions when IV drops (profitable)
• Avoid selling before IV spikes (earnings, etc.)

Gamma: Delta's Accelerator

Gamma measures how fast delta changes when the stock moves $1.

Example: Gamma of 0.05 means delta increases/decreases by 0.05 when stock moves $1.

Key gamma facts:

• Gamma is highest for ATM options
• Gamma increases dramatically near expiration
• High gamma = more risk of sudden delta changes

Wheel trading application:

• Avoid high gamma (short-dated ATM options)
• Target 30-45 DTE to minimize gamma risk
• Watch gamma carefully the week of expiration

Greeks Interaction Example

You sell a 30-delta put with 30 DTE:

Day	Stock Price	Delta	Theta	Position
1	$100	-0.30	-$5	Neutral
10	$100	-0.28	-$7	Theta working
20	$97	-0.45	-$10	Stock down, delta increased
30	$102	-0.15	N/A	Expires OTM, keep premium

IV Rank and IV Percentile

Two important metrics beyond the basic Greeks:

IV Rank: Where current IV sits relative to 52-week range

• IV Rank 80 = IV is in the top 20% of its annual range
• High IV Rank = good time to sell options

IV Percentile: % of days over past year with lower IV

• IV Percentile 90 = IV was lower 90% of the time
• High percentile = elevated IV, good for sellers

Practical Greek Guidelines for Wheel Traders

Greek	Target Range	Why
Delta	0.20-0.30	Balance probability and premium
DTE	30-45 days	Optimal theta, manageable gamma
IV Rank	> 30	Elevated premium
IV Percentile	> 50	IV above average

Using Greeks for Strike Selection

Instead of guessing, use delta to guide your strike selection:

1. Determine your probability tolerance (how often willing to be assigned)
2. Find the corresponding delta (30% assignment = 0.30 delta)
3. Screen for that delta range
4. Compare premium across strikes meeting criteria

Greek Monitoring Tools

Our screener displays key Greeks for every option:

• Delta for probability assessment
• Implied volatility for premium evaluation
• Days to expiration for time management

In the next lesson, we'll cover options tax implications.