The profitability of chain hotels plunged dramatically during what TRI Hospitality Consulting described as a "dismal August".
Of the 10 cities monitored in its monthly Europe HotStats survey, only London and Munich hotels managed to boost income before fixed charges per available room (IBFCpar).
Profitability in the two cities increased 2.5% and 32% to £79.03 and £45.10 respectively, with London emerging as the most profitable city in the survey.
A meeting of the European Society of Cardiology Congress, which attracted 25,000 visitors, was credited for helping Munich buck the general downward trend.
Occupancy declined across all 10 European cities except for Hamburg, which saw a marginal increase in demand of 0.5%.
The biggest falls in profitability were in Prague (down 49.2%), Vienna (down 46.2%) and Warsaw (down 38.7%).
David Bailey, deputy managing director at TRI, said: "It's the first time this year we have seen such large declines in occupancy."
By Angela Frewin
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