German businesses' expectations about the six months ahead have seen the biggest improvement for at least 18 years, as a generally brighter mood points to robust third- quarter growth in Europe's biggest economy.

The Munich-based Ifo institute said yesterday that its closely watched business climate index had risen for a fifth consecutive month, from 87.4 in July to 90.5 in August. That was the highest since September 2008, before the intensification of the global economic crisis following the collapse of Lehman Brothers.

The part of the survey covering expectations about the next six months rose even faster, from 90.4 to 95.0 – the biggest monthly rise since comparable data started in 1991. There was also a second monthly rise in businesses' assessment of current conditions, which as recently as June stood at the lowest level since the survey started in 1991.