The bitcoin rally continued Monday, and investors are betting it will go even higher.

Bitcoin was trading at more than $16,000 early Monday morning, up about 8%. And bitcoin futures, which started trading Sunday on the CBOE, showed that investors are betting the cryptocurrency will continue to climb in the coming months.

The January futures price was about $17,800, or about $1,500 above Monday’s spot price. The futures price for February and March were even higher, around $18,000 for each. As bullish as those prices are, they are down from Sunday’s price for February and March contracts, which had topped $19,000.

Futures are contracts that let investors buy or sell something at a specific price in the future. These futures are unusual in that, unlike traditional commodities such as oil or agricultural products, bitcoins aren’t physical assets. And unlike traditional currencies, there isn’t a central bank that backs bitcoin. They are created on computers using complex algorithms and recorded in a digital ledger.

Offering futures contracts for bitcoin allows investors to speculate on the digital currency’s price without actually owning any bitcoin. It also gives investors who believe that the run-up in price has produced a bitcoin “bubble” a chance to place a bet that bitcoin will soon fall in value.

Yes, it’s a new era for investors hoping to get in on the bitcoin game with fluctuations in value seemingly becoming the norm.

And the wild ride isn’t likely to end soon, as WRAL TechWire reported on Friday.

It’s the first time a government-regulated exchange has given the green light to trading for a bitcoin-backed security.

The CBOE’s competitor exchange, the Chicago Mercantile Exchange, will start trading its own futures on Dec. 18.

Chicago-based CBOE tweeted Sunday that its website was receiving “heavy traffic” after trading began. But it also added that all trading systems were “operating normally.”

The start of trading was a historic move. Unlike traditional commodities, bitcoins aren’t physical assets. And unlike traditional currencies, there isn’t a central bank that backs bitcoin.

Digital, unregulated

Bitcoins live on computer servers. They are produced by complex algorithms and recorded in a digital ledger.

Bitcoin, whose price has soared roughly 1,500% since the start of the year, got a lift from the new activity on the Chicago exchange.

It jumped about 8% in less than 10 minutes – to more than $15,700 – after the futures trading began, according to data from CoinDesk, which values bitcoin based on data from four exchanges.

By late Sunday, it was trading above $16,000. And on the futures exchange, contracts expiring next month were trading above $18,000.

Some leading economists and financiers are calling bitcoin a bubble and a fraud, but industry insiders say they think it’s only going to get bigger as it gains more widespread acceptance.

Currently, bitcoins are bought and sold on unregulated virtual exchanges — and it’s been extremely volatile.

Last week, in the run-up to its futures trading debut, bitcoin’s value soared on some exchanges from less than $10,000 to $17,000 before dropping back to near the $15,000 mark, spurring renewed warnings of a bubble.

Stephen Bielecki, an attorney with Kleinberg Kaplan, told CNNMoney this weekend that offering bitcoin futures may help “rationalize” the price.

Futures are contracts that let investors buy or sell something at a specific price in the future.

Offering futures contracts for bitcoin allows investors to speculate on the digital currency’s price without actually owning any bitcoin. That’s good news for mainstream investors who want to place their bets on bitcoin, but may be nervous about purchasing the actual currency.

The option also gives investors an easy way to bet against bitcoin, which could snap its streak of nearly unfettered gains.

There’s been a few sharp dips, but bitcoin’s rise has been stunning. In 2011, it once traded at less than a dollar, according to CoinDesk.

The CBOE futures do not involve actual bitcoin; they’re securities that will track the price of bitcoin on Gemini, one of the larger bitcoin exchanges.