Joby Aviation's Stock Dives 1.32% as Liquidity Slumps to 158th Rank Amid eVTOL Sector Volatility

On October 9, 2025, , marking a drop in investor sentiment amid subdued trading activity. , , ranking it 158th in terms of liquidity among listed equities. The reduced participation suggests limited short-term momentum despite ongoing market focus on the (eVTOL) sector.

Analysts noted that the decline aligns with broader volatility in high-growth tech stocks, though specific catalysts for Joby’s performance remain unclear. The company’s recent highlighted progress in certification timelines, but market participants appear to be weighing near-term execution risks against long-term potential. Institutional positioning data showed mixed signals, with some large holders trimming exposure ahead of key technical levels.

To conduct this study properly, a systematic approach is required. A 500-stock portfolio must be constructed and rebalanced daily to capture real-time liquidity dynamics. The current back-test framework operates on single-ticker analysis or index/ETF proxies, necessitating clarification on the methodology. Two options are available: (1) leverage an existing high-volume index like SPY with a one-day holding rule, or (2) create a daily-rebalanced of the top 500 most liquid stocks. The latter offers greater precision but requires multi-asset portfolio capabilities beyond current system constraints. Finalizing the implementation preference will determine the accuracy and scope of the back-test results.