Kevin Tyrell, Head of Equities Strategy and Research, NYSE
With the quarterly expiration approaching on Friday, we reviewed trading from the December expiration to see shifts in price discovery behavior. One widely-known market structure feature is the increase in volume on inverted venues at the end of the trading day, when inverted venues can approach 20% of S&P 500 volume at certain points.
However, during key trading periods such as quarterly expirations, the shares available at primary exchanges1 far exceeds that of inverted venues. We looked at the December expiration’s average quoted size at the NBBO from primary exchanges and inverted venues, and find that primary exchanges’ quoted size at the end of the day increased 38% vs. a standard day2 while inverted venues increased just 18%.
This additional pre-trade displayed liquidity results in more intra-day trading activity flocking to the primary exchanges. Primary exchanges see an increase in volume every day heading in to the closing auction, and the trend is more dramatic on event days such as an expiration. The below chart shows shares trading in the S&P 500 by time period, exclusive of closing auction volume.
This is the “liquidity begets liquidity” argument on display, with greater displayed size enticing more liquidity-seeking flow. This increasing order volume allows limit order queues to process more quickly, a topic we’ll revisit in a future post.
1“Primary exchanges” refers to trading on the listed market (e.g., NYSE trading NYSE-listed and Nasdaq trading Nasdaq-listed).
2“Standard day” represents an average of December 1st - December 22nd trading activity, excluding December 15th
Following the record-setting 40.1 million average daily volume (ADV) in the 1st quarter of this year, Q2 2021 options volume was the 2nd highest of all-time with 37.6 million contracts traded per day. Robust volume was driven in part by market anticipation of a potential earlier rise in interest rates and Fed tapering, as well as increased volume in options on new issues and continued activity in retail-focused stocks.
After-hours trading has been a larger piece of the total trading volume since the onset of the pandemic, with retail presence growing stronger and earnings announcements becoming less of a factor. In this post, we examine the impact of these shifting dynamics on after-hours price discovery and order behavior.
The surge in market volatility and trading volumes since the onset of the pandemic in March 2020 has impacted numerous aspects of equity market trading. One less-studied area has been after-hours trading. After-hours has also seen changes in order flow trends and influences, and here we examine trends and shifts occurring in these sessions.