Electric car maker Tesla (TSLA) took an impairment charge of $51 million in the third quarter to account for its bitcoin holdings.

• Elon Musk’s electric vehicle company reported no new sales or purchases of digital assets, according to its 3Q earnings presentation. The company currently holds $1.26 billion in bitcoin.
• According to accounting rules for digital assets, if the price of an asset falls during the quarter a company must report an impairment, but if the price increases it is not reported as a gain on the balance sheet.
• Bitcoin gained roughly 30% in the third quarter, rising to about $43,800.
• Tesla announced in February it had purchased $1.5 billion worth of bitcoin. Later in Q1, the company trimmed its bitcoin position by 10%, a sale that boosted that quarter’s earnings by $272 million. Tesla also didn’t buy or sell any bitcoin in the second quarter.
• Overall, Tesla’s adjusted Q3 earnings per share came in at $1.86 versus $1.62 expected, according to FactSet, while revenue came in at $13.76 billion vs. $14.00 billion expected.
• Tesla’s share price fell 0.2% to $864.22 in after-hours trading on Wednesday.

UPDATE (Oct. 20, 21:03 UTC): Added information in the second bullet point.