Investing.com - A weekly report by Finder.com says more than 80% of cryptocurrencies dropped in price in the past seven days.Prices fell by an average of 19% in the week ended June 25, the website’s Weekly Coin Analysis said.Trading volume also dropped, falling by 6% from the previous week. Even though the weekly trading volume was down just 6%, volume has halved since the end of April when the first such report was released.Bitcoin, Tether, Ether, EOS and Bitcoin Cash were the top five traded cryptocurrencies.The five cryptos with the biggest price declines were Bitcoin, Bitcoin Cash, Maker, Ethereum and Dash.The top five price gainers were Ethereum Classic, Docademic, Basic Attention Token, Enigma and Centrality.