Do tides correlate with S&P price movement? Sometime they do with absolute accuracy and sometime they don't and go in opposite directions.
As of recently, S&P price movement and tides are correlating well for key turning points (but may not in the future). Consider the below chart covering the last 150 trading days. The blue line is the daily S&P price level while the red line is derived/computed from tide forecast data available from NASA. The forecast data is available for months in advance and can be used for market timing if you tend to believe in the impact of moon and sun on financial markets using tides as the barometer.
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| S&P and Tides - 04/01/2019 |
Analyzing the tide data reveals 3 dominant fixed cycles that are responsible for the whole structure. Even if you have old data on tides, it can be used to build the cycle model and extrapolated to provide future predictions. See below chart where the blue curve is the real tide data while the red curve is the cycle model developed from it with extrapolation.
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| Tides and Cycles behind them |
Few things to note:
- Tide data only provides cyclical behavior within a 28-30 day window. They cannot provide any guidance or predict long term trends covering weeks/months/quarters/years. Hence, they are not of significant importance for medium-to-long term trading or investing.
- Each up or down move in tide data is of similar degree. S&P may not change by similar degree or might not even budge at all in the same direction. And when the two don't correlate at all, both may move in opposite direction which would be impossible to know apriori.
Still it doesn't hurt to monitor them and gauge what tide S&P is on!