# Unusual OI growth shift toward puts

Canonical: https://halfonadouble.com/screens/unusual-put-oi-growth-shift
Data through: 2026-10-16 close
Publisher: Half on a Double

Where did the balance of call-versus-put OI growth shift unusually far toward puts on Oct 16, 2026?

Rising put OI with a growth advantage over calls, and a call-minus-put growth gap at least two standard deviations toward puts relative to its own prior year. The gap has its own standardized history; subtracting the separate call and put z-scores is not this measure. Requires 200 prior comparisons, 100,000 current contracts and 1,000 contracts on each side at the prior close. This measures the OI balance, not implied-volatility skew.

5 published matches, in the same order as the HTML screen.

| Ticker | Close (USD/share) | Open interest (contracts) | Call / put growth and gap surprise |
| --- | --- | --- | --- |
| [TGB](https://halfonadouble.com/stock/TGB) | 7.97 | 101,876 | Calls -5.9% · puts +31.0% · gap -36.9 pp · gap -9.01σ |
| [IYR](https://halfonadouble.com/stock/IYR) | 97.39 | 191,092 | Calls -20.4% · puts +40.4% · gap -60.8 pp · gap -7.74σ |
| [XLP](https://halfonadouble.com/stock/XLP) | 87.62 | 648,584 | Calls -4.4% · puts +24.0% · gap -28.4 pp · gap -4.30σ |
| [GRAB](https://halfonadouble.com/stock/GRAB) | 2.94 | 2,228,242 | Calls -5.0% · puts +5.7% · gap -10.7 pp · gap -2.98σ |
| [AKAM](https://halfonadouble.com/stock/AKAM) | 87.81 | 292,423 | Calls -2.2% · puts +5.3% · gap -7.5 pp · gap -2.52σ |

An em dash means unavailable or not applicable, not zero. [Definitions and limitations](https://halfonadouble.com/methodology.md).