Investors in cryptocurrencies have lost nearly $500 billion (£397 billion) in a miserable year for the controversial asset class, experts said on Tuesday.

A year ago this week the most prominent crypto, bitcoin, hit a record high, changing hands for almost $20,000 each as a flood of speculative cash fuelled a bubble.

But bitcoin has slumped more than 80% since then, with latecomers to the party suffering major financial damage in a staggering destruction of value.

Cryptocurrency broker Global Block said: “Cryptomarkets continue to leach value, with overall market cap across cryptos now threatening to break down through the $100 billion level.

“Bearing in mind a year ago the overall market cap was nearly $594 billion, it has been one very bearish year.”

This week Erik Finman, 19, one of the world’s youngest bitcoin millionaires who first bought the currency when he was 12, said: “Long term, it’s dead.”

Bitcoin was created in 2008 by Satoshi Nakamoto, although the name is believed to be a psuedonym for the cryptocurrency’s creators.