In afternoon trade, the S&P/ASX 200 Index (ASX: XJO) is on course to end the week with a gain. At the time of writing, the benchmark index is up 0.3% to 8,402.5 points.

Four ASX shares that have failed to follow the market higher today are listed below. Here's why they are falling:

Coronado Global Resources Inc (ASX: CRN)

The Coronado Global share price is down over 6% to 66.5 cents. This coal miner's shares have hit a 52-week low today after the market responded negatively to its quarterly update from earlier this week. While Macquarie acknowledges that the company's update fell short of expectations, it remains positive. As a result, it has retained its outperform rating and $1.00 price target Coronado Global's shares this morning. This implies potential upside of 50% for investors from current levels.

Kogan.com Ltd (ASX: KGN)

The Kogan share price is down almost 13% to $5.23. This follows the release of a half year trading update from the online retailer this morning which revealed earnings that were well short of consensus estimates. Kogan reported a 10.3% increase in gross sales to $492.5 million and a 17.5% lift in adjusted EBITDA to $25.3 million. However, the latter was short of the consensus estimate for adjusted EBITDA of $28 million for the first half.

Nanosonics Ltd (ASX: NAN)

The Nanosonics share price is down 1.5% to $3.70. This appears to have been driven by a broker note out of Morgans this morning. According to the note, the broker has downgraded the infection control company's shares to a hold rating with a $3.75 price target. This follows the release of a solid half year trading update earlier this week from Nanosonics. However, with its shares rallying strongly in recent times, the broker has downgraded them on valuation grounds today.

Regis Resources Ltd (ASX: RRL)

The Regis Resources share price is down almost 6% to $3.02. Investors have been selling the gold miner's shares for a couple of reasons today. One is the broad weakness in the gold industry today which has seen most gold shares drop into the red. So much so, the S&P/ASX All Ords Gold index is down 1.3% on Friday. In addition, this morning Citi retained its neutral rating and $3.00 price target on the company's shares following the release of its quarterly update this week. This is now largely in line with where Regis Resources' shares are trading.