Thinking out loud about the pure and simple #MarketTiming with the NYMO/NYSI and Stocks, ETFs

The stock market either goes up or goes down, taking its stocks and ETFs with it. And yet It is amazing how difficult it is to recognize that simplicity.

Michael Petryni
3 min readOct 25, 2023


Short-term swing trading: When the NYMO turns up, it is time to buy stocks on the next open. When the NYMO turns down it is time to sell stocks on the next open.

Longer-term swing trading: When the NYSI turns up it is time to buy stocks on the next open. When the NYSI turns down, it is time to go to cash or to go short on the next open.

Most stocks and ETFs move with the market.

Simple as that.

Okay, okay, everyone went short five trading days ago when the NYSI turned down, right?

Surely, since I’ve been preaching this here for at least a couple of years.

I bring this up only to stress, once again, to my mind, there is no better market-timing tools than the McClellan Oscillator (the NYMO) and its Summation Index (the NYSI).

One of my sons once suggested to me that I sell my market-timing signals for a lot of money.



Michael Petryni

Journalist, film critic, screenwriter, proprietary trader seeking simplicity in trading.