A bitcoin logo on a mobile phone.Omar Marques | SOPA Images, LightRocket | Getty ImagesBitcoin just climbed past $18,000 for the first time since December 2017, extending a wild run for the cryptocurrency this year.The price of bitcoin was trading about 8.6% higher Wednesday morning at $18,172, breaching a level it hasn’t hit since Dec. 20, 2017, according to data from industry site CoinDesk.Bitcoin has been on a tear in 2020, skyrocketing over 150% in a jump crypto enthusiasts have accredited to unprecedented monetary and fiscal stimulus in response to the Covid-19 crisis, as well as interest from big-name investors such as Paul Tudor Jones and Stephen Druckenmiller.It is now creeping up toward the all-time high of $19,783 which it posted in a late 2017 rally that saw the values of several cryptocurrencies surge. After hitting that milestone, the bubble burst and bitcoin plummeted to as low as $3,122 the following year.But many crypto fans claim things are different this time. They’ve cheered big moves in the industry from the likes of Fidelity Investments, Square and PayPal.PayPal recently started letting its users buy, hold and sell virtual currencies. The payments giant is set to enable shopping with crypto early next year.Bitcoin’s market value — which is calculated by multiplying the total number of bitcoins in circulation by the price — now stands at $337.2 billion, higher than the $331.8 billion it hit in December 2017, according to CoinMarketCap data.”Bitcoin’s market cap is now higher despite the cryptoasset being worth slightly less because there are more bitcoins in the system than there were in 2017,” Adam Vettese, market analyst at online investment platform eToro, said via email on Wednesday. “The supply has expanded by roughly 10.75% since its last record.”The total number of bitcoins that will ever be produced is capped at 21 million. The cryptocurrency underwent a key technical event in the spring known as the “halving,” which saw the amount of bitcoins rewarded to the so-called “miners” who add bitcoin transactions to its public ledger get cut in half.