March 31st, 2021 Options Expiration -- SPDR S&P 500 ETF Covered Call Position Assigned

Yesterday, the March 31st, 2021 (a quarterly options expiration date) Covered Call position in the SPDR S&P 500 ETF (ticker SPY) expired in-the-money, so the 100 shares of SPY were assigned (i.e. sold) at the $380.00 strike price.  As detailed below, the return-on-investment (ROI) result was  +0.7% absolute return (equivalent to +15.3% annualized return-on-investment for the 17 days holding period).   

It is always desirable to achieve a positive return-on-investment, but the +15.3% aroi in this case is below the Covered Calls Advisor's minimum target of greater than +20.0%.  Since ETFs (such as SPY) hold so many stocks, their risk (and therefore also their Implied Volatility) is lower than the Implied Volatility of the individual stocks contained in them.  So because the Implied Volatility for individual stocks is higher, the potential return-on-investment when establishing Covered Calls with individual stocks is also higher.  This is the primary reason the Covered Calls Advisor prefers buying stocks (not ETFs) for Covered Calls positions.    

SPDR S&P 500 ETF (SPY) -- Covered Call Position Closed by Assignment at Expiration

The buy/write transaction was as follows:
03/15/2021 Bought 100 shares of SPDR S&P 500 ETF @ $392.22 per share 
03/15/2021 Sold 1 SPY March 31st, 2021 $380.00 Call option @ $13.64 per share
Note: the Implied Volatility of the Call options was 17.2
03/19/2021 Ex-distribution of $1.2778 per share
03/31/2021 SPY Call option expired in-the-money so the 100 SPY shares were assigned (i.e. sold) at the $380.00 strike price.

Two possible overall performance results (including commissions) would be as follows:
Covered Calls Cost Basis: $37,858.67
= ($392.22 - $13.64) * 100 shares + $.67 commission

Net Profit Components:
(a) Options Income: +$1,364.00
= ($13.64 * 100 shares)
(b) Distribution Income (SPY shares assigned on March 31st options expiration date): +$127.78
=  $1.2778 per share x 100 shares
(c) Capital Appreciation: -$1,222.00
= ($380.00 - $392.22) * 100 shares

Total Net Profit (SPY shares assigned on March 31st options expiration date): +$269.78
= (+$1,364.00 options income +$127.78 dividend income -$1,222.00 capital appreciation)

Absolute Return: +0.7%
= +$269.78/$37,858.67
Equivalent Annualized Return: +15.3%
= (+$269.78/$37,858.67)*(365/17 days)