Karen uses a unique method to manage the allocated
trading capital. She pretends the market dropping over 12% in her margin crash
tests while TOS portfolio policy stated a minimal 10% drop for portfolio margin
using broad index based vehicles. Using the TOS analyzer, she watches potential
crash loss in the portfolio against the net liquidation value of her account as
shown in the following picture. On the Analyzer tab, the daily P&L numbers
at 10% up and 12% down must not exceed net liquidation value.
In the above chart, the +6% and the -10% slices are
broker SPX stress test prices. All the other slices beyond them are Karen’s
stress test points. In order to maintain sufficient adjustment capital during
market sell-offs, Karen lowers her stress test point below the 10% down point
by another 100 to 200 offset points, depending on the long term market volatility
condition.
- · 2013 Crash price (cushion) = (Current price – 100) x 88% due to lower volatility.
- · 2011 crash price = (current price – 200) x 88% due to higher volatility.
According to Figure 2: SPY and Its Implied Volatility Since 2008 shown before, there are 2 levels of IV in the past few years. Starting
at January of 2013, the volatility made a lower low and stayed within a much
narrow and lower channel ever since. Thus, it makes sense to use the smaller
and pretended drop of 100 points of SPX in the crash price calculation starting
at the beginning of 2013.
In my personal opinion, it will be a good time to
switch to the larger drop of 200 points of SPX when the IV makes a higher low
and forms a newly elevated channel in the future. If the volatility VIX is
generally lower to a level of 11 and 12 at its bottom (this is a long bull
market condition), the 100-point offset is used. If the volatility is higher to
a level of 13 at the bottom of the VIX, the 200-point offset is used.
Additionally, it is easier in the TOS analyzer and
more conservative if a Karen style trader uses the following formula to
determine the crash price. Karen does not offer complete details of her trading
system but encourages traders to come up with the system that they are
comfortable with.
- · crash price = current price x 88% - 100 or 200
According to the statements in the interview, the
12% crash down price has a probability of ITM of 5% approximately. Let’s
investigate it using today’s data as a specific example. The SPX price is 1900
on May 25, 2014. The 12% down SPX price based on Karen’s stress test formula is
1584. There is a 53 DTE July 1585 put option of ITM probability of 2%. Although
the probability to expire ITM on July expiration date is quite low, the
probability to touch the strike of 1585 is a bit higher, probably twice the
amount of expiration probability to 4 to 10%.
Now, we can study the margin requirement and its
changes for the hypothetical position shown in the above chart. It’s clear that
the opening or initial margin requirement is $6,291. The “Explain Margin”
section embedded in the chart indicates the margin requirement changes from
-10% to +6% of SPX price changes.
However, if SPX drops to 1565, a level looked by Karen
style trader, the loss would be $19,968. Karen would make sure the loss number
is less than the net liquidation value of the account on the opening day with
the proper size of contracts. This amount of the loss would be higher than the
initial margin requirement of $6,291. As of today, I’m not sure what would the
new margin requirement be in this scenario. Would it become 4.9 times of the
initial margin requirement to $30,869? How margin requirement changes in market
crash conditions still needs investigation in the future.
Although the PM requirement changes according to
market conditions for existing portfolio and the changes may be different for
various brokerage firms, the net liquidation value of an short option account
is more deterministic. Therefore, the net liquidation value is used as the
basis for comparing the daily P&L number in Karen style trading.
It should be noted that the initial margin $6,291 of
the position is dictated by the short call option at an upside movement of +6%
of SPX price as the down side movement of -10% requires a less amount of margin
of $6,266 only. It implies more puts can be sold in trade adjustments if market
tanks, because short put options require significant less margins. This is naturally
helpful to obtain more credits to cover the deficit of put option rolling down
or out when market crashes.
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