Note: The 1D 25Δ Skew for #BTC options has once again approached -10... Are we about to draw the door down again? Short version: Over the past 3 months, every time this indicator has entered the extreme negative zone, the price has subsequently dropped (see Chart 2). Detailed explanation: For the past month, I've been closely studying the 25Δ Skew on laevitas. The main calculation method is: Normalized Skew = (IV_25Δ Put - IV_25Δ Call) / IV_ATM Previous explanations and research are referenced below, so I won't repeat them here. Last week, just like this week, the market was in a very boring sideways consolidation on Saturday. However, amidst the calm, the 1D 25Δ Skew suddenly dropped to around -10. The result was clear: On Sunday, the price dropped from 90k to 88k. Then on Monday, after rebounding to 90k, it continued down to 85k. (Whether the Monday drop from 90k to 85k is related is uncertain, but the Sunday drop from 90k to 88k is strongly correlated.) Today, the same scenario from last Saturday is repeating: during a boring consolidation, the 1D 25Δ Skew quietly dropped to -13 again (see the blue circle in Chart 1). (For the logic behind the decline in 25Δ Skew, see the references.) Is this again a sign of an upcoming "door-drawing" (i.e., a price drop)? If so, I've conducted a backtest on the historical data from the past 3 months (covering from before October 11th to now). Indeed, there is a strong correlation. See Chart 2. (Note that due to the data granularity on laevitas, the 3-month historical data is only available every 4 hours. Therefore, in the backtest in Chart 2, several downward peaks don't reach -10 but are around -6. However, this doesn't affect the backtest results.) In summary, just the conclusion: Over the past 3 months, every time the 1D 25Δ Skew dropped rapidly, it was followed by a downward price movement. Conversely, every time the 1D 25Δ Skew rose rapidly to a peak, it was followed by an upward price movement. You can refer to Chart 2 for verification.