The VOO put/call ratio crashed to 0.66 on May 11 — its lowest in 52 weeks. That single data point captures the market's mood better than anything else in this snapshot.
The 20-day average PCR sits at 1.47. Monday's reading is 2.6 standard deviations below that mean. Traders are buying calls at a pace not seen all year. The S&P 500 ETF has gained 8.8% in one month, and the options market is leaning hard into the rally.
The PCR shift is striking in its speed. From May 4–8, the ratio held above 1.77 — deep in put-heavy territory. Then on May 11 it collapsed to 0.66 in a single session. The only comparable single-day drop in the history window was April 30, when the ratio briefly touched 0.66 before reverting.
That May 8 reading of 1.85 was the 52-week high. Monday's 0.66 is approaching the 52-week low of 0.57. The full range was crossed in three trading days.
The cost-to-borrow for VOO doubled week-on-week to 0.35%. That sounds dramatic. In context, it isn't.
Short interest sits at just 0.40% of free float — a negligible figure for a passive index ETF of this size. Availability remains extremely loose. The borrow market for VOO is structurally oversupplied; CTB moves at this level reflect daily micro-fluctuations rather than genuine demand pressure from bearish positioning.
Short interest itself fell more than 33% over the past month, even as it ticked up slightly this week. The ORTEX short score is stable at 25.7 — well below levels that would indicate meaningful bearish conviction.
The lending signals are not corroborating the options bullishness. They're an artifact of a very lightly shorted, highly liquid vehicle.
What to watch: Whether the PCR sustains below 1.0. A reversion toward the 20-day average of 1.47 would suggest the options positioning was event-driven rather than a durable shift in sentiment.
See the live data behind this article on ORTEX.
Open VOO on ORTEX →ORTEX Market Intelligence content is generated by AI from a snapshot of ORTEX's proprietary data. Content is informational only and does not constitute investment advice.
