16-Week Cycle in Markets The ~16-week cycle (≈112 calendar days / ~80 trading days) shows up clearly in many instruments, including SPX. What’s driving it? Many cycle analysts look to the solar system for stable periodicities. Mercury’s synodic period is 115.9 days — strikingly close. Is there a real link? And if so, what’s the mechanism — direct, or indirect via subtle modulation of solar plasma/activity? More questions than answers at this point.
Published Jul 26, 2026Updated Jul 26, 20262 min read
16-Week Cycle in Markets The ~16-week cycle (≈112 calendar days / ~80 trading days) shows up clearly in many instruments, including SPX. What’s driving it? Many cycle analysts look to the solar system for stable periodicities. Mercury’s synodic period is 115.9 days — strikingly close. Is there a real link? And if so, what’s the mechanism — direct, or indirect via subtle modulation of solar plasma/activity? More questions than answers at this point.
