As reported in the Evening Standard [standard.co.uk], the Bank of International Settlements published an annual report with four criteria to continue economic growth. However, it was rather overshadowed by a statement in the appendix (reported here [cnbc.com], here [bloomberg.com], here [nexusnewsfeed.com], here [cityam.com], here [reuters.com] and elsewhere) where cryptographic currency was described as a "combination of a bubble, a Ponzi scheme and an environmental disaster".
I agree [soylentnews.org] and so does a Canadian electricity company [soylentnews.org].