Premium Market Analysis, Trader Education, Software, and Trading Strategies. Thirty Years Of Skin In The Game

Market Statistics

The S&P 500 Broke A Historic Win Streak of 15 Up Mondays

Photo by

A historic, yet unexplainable, win streak of 15 consecutive Mondays was broken on October 23, 2023. Here are the details.

The S&P 500 index fell 0.17% on Monday, October 23, 2023, after a historic winning streak of 15 consecutive Mondays.


The gain on 15 consecutive Mondays was 6.5% versus a loss of 5.2% for the index in the same period. This is a significant price action anomaly.

Probably, the anomaly could be justified on the basis of investor optimism at the start of the week. Some traders could assert this was the result of algo manipulation to trap bulls and weak hands. Or it could be the result of randomness. We will never know.

Note that from 1945 to 1986, Mondays generated staggering losses. But that changed after Black Monday.


In other words, Mondays were bearish before Black Monday but became more bullish after Black Monday. Do not look for an explanation; this is the market.

We never try to identify the causes of price action. It is an exercise in futility since the market is a highly non-linear stochastic process. But some calendar effects are interesting.

Price Action Lab Blog Premium Content

Subscribe for immediate access to hundreds of articles. Premium Articles subscribers have immediate access to more than two hundred articles, and All in One subscribers have access to all premium articles, books, premium insights, and market signal content.



Disclaimer:  No part of the analysis in this blog constitutes a trade recommendation. The past performance of any trading system or methodology is not necessarily indicative of future results. Read the full disclaimer here.

Charting and backtesting program: Amibroker. Data provider: Norgate Data

If you found this article interesting, you may follow this blog via RSS, Email, or  X.