The report concentrates on residual values for two and three-year-old models and includes typical company cars in the small, lower medium, upper medium and executive segments.
It tracks residual value movements and compares them to those of 12 months ago and it also provides separate data for petrol and diesel models.
Although the premium for diesel over petrol has reduced slightly, diesel models on average are still achieving 30% more.
The report says: 'There is close correlation between two and three-year residual value differences across Europe. The main exception to this is Belgium where high taxation on younger vehicles drives down two-year RVs.
'Portugal has the highest values,' the study adds, 'particularly for older vehicles in a country where vehicles tend to be kept by their owners for a longer period. The UK also has high values, largely driven by the relatively high new car prices.
'In percentage terms the UK, however, has the highest depreciation rates.'
Austria and the Netherlands were also found to have 'significantly' above average values, particularly for three-year cars.
'In contrast to Portugal, Spain has significantly lower used car values, partly driven by lower retail new car prices,' the report adds.
Eastern European markets, in particular Poland, also tend to have lower values, perhaps 'due to the relatively underdeveloped nature of those markets', says the report.
'Residual value performance across Europe remains mixed and, on average, declining slightly overall. Three-year values are performing marginally better than two-year values, particularly diesels.
'After a period when the gap reduced slightly, there is no sign of any further significant movement in the premium for diesel models over petrol models, which in most markets is over 30%.'
According to the survey, Italy is experiencing the largest decline in two-year values (-4.3%) with falls also noted in France, Spain, Belgium and Poland. The Netherlands and Czech Republic are also showing the largest increases followed by Germany and Austria.
'Three-year values follow a similar pattern, except for the UK where three-year values are performing much worse than two-year values. Belgium, Netherlands, Portugal and Czech Republic are all showing strong increases.'
Eurocarprice.com found that performance by segment is also mixed, with the executive segment showing the largest declines.
Diesel winners in residuals ratings
Three-year-old diesel cars in the small and executive segments are achieving the highest average residual values across Europe.
Used values for typical fleet diesel models in the upper medium segments have improved over the past 12 months and achieve on average 53% of their new price, compared to 46% achieved for their petrol equivalents.
In the lower medium segment, diesel cars retain on average 52% of their original price after three years while petrol models retain 47%.
The top performers in each segment for three-year-old cars were:
Comparisons of residual value movements over the past 12 months show a mixed picture of the most improved performers.
For example, while the Peugeot 406 diesel model's residual value increased by 6.8%, the biggest jump noted in the upper medium segment, the petrol version increased by just 0.3%.
And while the diesel version of the soon-to-be discontinued Opel Omega's used value increased by 2.3% over the past year, the study found, its petrol equivalent fell by 7.2%.
Both petrol and diesel models of the old Nissan Primera fell, by 7.9% for the diesel and 4% for the petrol, but this is a result of a new model introduced this year.
Residuals for popular fleet model, the Opel Vectra, have slightly improved for the diesel model, up by 0.4% from 12 months ago, but residuals for its petrol version have tumbled by 6.9%. Again, this is likely to be as a result of a new model introduction this year.
Ford Mondeo's residuals have fallen for both three-year-old petrol and diesel models, but again would have had an impact on the launch of a new model. The diesel value has fallen by 1.9% compared to a year ago, and the petrol model's used value has fallen by 1.2%.