As the price of the flagship cryptocurrency Bitcoin ($BTC) hovers around the $99,000 mark the Coinbase Premium Index, which measures the price difference between BTC on Coinbase and other exchanges, has “disappeared.”

According to a post from CryptoQuant analyst “maartunn,” the index disappeared “as soon as Bitcoin tagged $98,000,” which means that spot exchange-traded funds (ETFs) will have to “step up” to “keep the price elevated.”

The Coinbase premium index is an indicator showing the price gap between Coinbase’s BTC/USD trading pair and Binance’s BTC/USDT pair. When the premium is positive, it shows buying pressure on the exchange is heating up.

A deeply discounted premium suggests weak buying pressure from American investors, a trend that has coincided with past Bitcoin price bottoms.

Back in July, the index was a key indicator in finding the cryptocurrency’s market bottom, as after the premium discount was negative the head of research at cryptocurrency brokerage FalconX, David Lawant accurately called BTC would see a “splendid” return in the next six to twelve months.

Since then, the cryptocurrency’s price has exploded from a little under $60,000 to now trade at $99,000 near the psychological resistance level of $100,000.