In afternoon trade, the S&P/ASX 200 Index (ASX: XJO) is on course to end the week deep in the red. At the time of writing, the benchmark index is down 1.4% to 7,537.5.

Four ASX shares that are falling more than most today are listed below. Here's why they are dropping:

The COG Financial Services share price is down over 6% to $1.25. This follows the release of the equipment finance company's quarterly update. COG reported a 6.9% decline in quarterly net profit after tax (before amortisation) for the three months ended 31 March. This is particularly disappointing as it marks a sudden and sharp slowdown in its profit growth. For example, during the first half, the company's profits were up 11% on the prior corresponding period. Management said: "Our Asset Management & Lending segment has achieved strong originations growth but has been adversely impacted by a margin squeeze due to increased funding interest rates on historical originations.".

The Karoon Energy share price is down almost 3% to $2.16. This energy producer is falling today after a disappointing quarterly update offset news of a jump in oil prices this afternoon. In respect to its update, Karoon Energy's total production for the quarter on a net working interest (NWI) basis came in at 3.11 MMboe. This was weaker than expected and forced management to downgrade its FY 2024 guidance. Karoon Energy's production in FY 2024 is now expected to be between 10.5 MMboe and 12.5 MMboe. This compares to its previous guidance of 11.2 MMboe to 13.5 MMboe.

The Netwealth share price is down 4.5% to $18.88. This appears to have been driven by a broker note out of Citi this morning. According to the note, the broker has downgraded the investment platform provider's shares to a sell rating but with an improved price target of $18.65. While Netwealth's quarterly update was stronger than Citi was expecting, it feels its valuation is full.

The Pilbara Minerals share price is down almost 2% to $3.84. This follows the release of the lithium miner's quarterly update this morning. Pilbara Minerals reported a 2% quarter on quarter increase in spodumene production to 179kt and a 3% lift in spodumene sales to 165.1kt. And as was expected, the miner reported a sizeable 28% decline in its realised average price to US$804 a tonne.