The few curious tourists in the viewing gallery at the Frankfurt Stock Exchange last week could probably sense what recent data have already revealed: even by the standards of the summer lull, these are quiet days for equity trading at the largest of Germany’s seven stock exchanges.

Floor-trading at the exchange, owned by Deutsche Börse group, was down 41 per cent year-on-year in the second quarter. Even on Xetra, Deutsche Börse’s larger electronic platform, volumes were 13 per cent lower last month than a year ago. The figures continued a trend of recent months that has disquieted some investors, sending shares in the Börse down about 50 per cent since December.