Early Assignment of Covered Calls Position in Morgan Stanley

I was notified via email early this morning by my broker (Schwab) that the three Morgan Stanley (ticker MS) August 8th, 2025 Call options were exercised yesterday.  Morgan Stanley's stock price increased from $140.46 when this position was established to $143.94 at yesterday's market close.  The original $1.30 time value in the Calls when the position was established had declined on yesterday's market close to $0.00.  So, with eight days remaining until the August 8th, 2025 options expiration date, the owner of these Calls exercised their option to buy the 300 shares at the $137.00 strike price in order to receive today's $1.00 per share ex-dividend.  Although I will not receive the ex-dividend, I am pleased with the +34.8% annualized-return-on-investment (aroi) result achieved since it slightly exceeds the maximum aroi that might have been achieved if this position instead had remained in-the-money and would therefore be assigned on the August 8th options expiration date.   

The post when this Morgan Stanley Covered Calls position was originally established is here.  

As detailed below, the return-on-investment result for this Morgan Stanley Covered Calls position was +1.0% absolute return in 10 days (equivalent to a +34.8% annualized return-on-investment).

Morgan Stanley (MS) -- Covered Calls Position Closed by Early Assignment

The buy/write transaction was:
7/21/2025 Bought 300 Morgan Stanley shares @ $140.46
7/21/2025 Sold 3 Morgan Stanley 8/8/2025 $137.00 Call options @ $4.76
Note: the Implied Volatility of the Call options was 21.9 when this buy/write transaction was executed.
7/31/2025 Three Morgan Stanley Calls were exercised on the last business day prior to today's July 31st, 2025 ex-dividend date, so the Call options expired and the 300 MS shares were sold at the $137.00 strike price.

The overall performance results (including commissions) for this Morgan Stanley Covered Calls position are as follows:
Covered Calls Cost Basis: $40,712.01
= ($140.46 - $4.76) * 300 shares + $2.01 commission

Net Profit Components:
(a) Options Income: +$1,425.99
= ($4.76 * 300 shares) - $2.01 commission
(b) Dividend Income (Three Call options exercised early on July 30th, the last business day prior to the July 31st ex-div date): +$0.00

(c) Capital Appreciation (Morgan Stanley Call options assigned early on July 31st): -$1,038.00
+($137.00 strike price - $140.46 stock purchase price) * 300 shares

Total Net Profit: +$387.99

= (+$1,425.99 options income +$0.00 dividend income -$1,038.00 capital appreciation); or

Absolute Return-on-Investment: +1.0%

= +$387.99/$40,712.01

Annualized Return-on-Investment: +34.8%

= (+$387.99/$40,712.01) * (365/10 days)