When the market looks back on the early months of 2014, hopefully the period will mark the apogee of wild guesses of the financial value of chat, microblog and messaging services. Rarely has so much communication about, well, communication produced so little in terms of hard facts. Hard landings are easier to find however: Sina’s Weibo has priced its partial spin-off to raise $285m and value the Twitter-like microblog at $3.8bn – more than 40 per cent below estimates just a month ago.

Weibo’s pricing should in theory bring any lingering optimists down to earth with a bump. Since it filed its prospectus a month ago, shares of its parent, Sina, have fallen 20 per cent.

Facebook, which bought WhatsApp for $19bn in February, is down 13 per cent over that time and Korea’s Naver, owner of Line, the third biggest messaging service, is off 8 per cent.