Open interest on the Perpetual Swap Decentralized Exchange (Perp DEX) fell sharply from $26 billion to under $14 billion following the crypto market flash crash on October 11, according to DefiLlama's on-chain data. This significant decline highlights the volatility and rapid shifts in the decentralized finance sector. In related developments, lending protocol fees hit a record single-day high of over $20 million last Friday, while decentralized exchange (DEX) weekly trading volume surged to more than $177 billion. However, total lending volume on lending protocols dipped below $50 billion, marking the first time since August.