Writing conundrums

We’re taking a break from our portfolio series and million sample simulations to return to a subject that we haven’t discussed of late despite its featured spot in this blog’s name—options. In this post, we’ll look at the buy-write (BXM) and put-write (PUT) indices on the S&P 500, as conceived, calculated, and published by the CBOE. Note: we’ve discussed the buy-write strategy in the past here and here. In those posts, we analyzed the performance of the buy-write relative to its underlying index, the S&P 500.

Skew who?

In our last post on the SKEW index we looked at how good the index was in pricing two standard deviation (2SD) down moves. The answer: not very. But, we conjectured that this poor performance may be due to the fact that it is more accurate at pricing larger moves, which occur with greater frequency relative to the normal distribution in the S&P. In fact, we showed that on a monthly basis, two standard deviation moves in the S&P 500 (the index underlying the SKEW) occur with approximately the same frequency as would be expected in a normal distribution.

SKEWed perceptions

The CBOE’s SKEW index has attracted some headlines among the press and blogosphere, as readings approach levels not see in the last year. If the index continues to draw attention, doomsayers will likely say this predicts the next correction or bear market. Perma-bulls will catalogue all the reasons not to worry. Our job will be to look at the data and to see what, if anything, the SKEW divines. If you don’t know what the SKEW is, we’ll offer a condensed definition.

Calling covered data

In our last post on covered calls we introduced the CBOE’s buy-write index (or BXM), whose underlying is the S&P500 index. We looked at some of the historical data, made a few comparisons between the index and the S&P, and noted that there was a report that analyzed the buy-write index. In this post, we’ll look at some of the findings from that report, which can be found on the CBOE’s website.

Who's covered

One of the simplest options strategies is known as the covered call. For this strategy, an investor who already owns a stock elects to sell (or write) an option contract to surrender that stock at a specified price (known as the strike) at some point in the future (also known as expiration). The sale of the contract generates income for the investor, not unlike when an insurance company receives premiums from selling an insurance contract.