Nearly all the leading cryptocurrencies took a nosedive in their market capitalisation in the third week of January. January 16th figures showed all the top 20 currencies falling in price, many by 10-20%, according to data provided by CoinMarketCap. In some cases prices dropped more than 20% over the following 24 hours. Ripple's XRP is perhaps the hardest hit, showing losses in excess of 25% on January 16th, and the price dropping on the following day to just over a dollar. Only days ago, Ripple was trading at over $3, and its chairman was being touted as one of the richest men on the planet.

The total market cap for all cryptocurrency tokens, not long ago pushing the $800bn level, is now closer to $500bn, and within the past 24 hours dropped by almost $200bn in one fell swoop. The massive market drop is illustrative of the general turbulence in today's cryptocurrency markets, as regulators and national governments step in to affect the performance of exchanges round the world. Bitcoin itself (BTC), listed as the largest cryptocurrency in the world by market cap, has fallen considerably, down some 13.6% on January 17th. Its price has dropped down to its pre-December levels of around $11,000.

Of the 100 cryptocurrencies ranked by volume on CoinMarketCap, only seven are reporting a price increase on January 17th.