The economic and financial situation remains the biggest challenge for car and commercial vehicle makers in 2010, and while declines in sales were observed across the continent, the sharpest decline was observed in Bulgaria, European Automobile Manufacturers' Association, ACEA, said in a media statement.Only 1201 vehicles were purchased in April 2010 in Bulgaria, or 50.8 per cent fewer than figures from April last year, which was the worst in Europe.In the first quarter, Bulgaria accounted for the third steepest decline after Romania with 56 per cent, and Hungary with 52.0 per cent. A total of 4557 vehicles were sold in Bulgaria in Q1, as opposed to 8543 in the first quarter of last year.Ireland, meanwhile, registered a 95 per cent rise for April, while Portugal, with 59.1 per cent, has the best statistics for the first quarter.And while any relevant forecasts remain difficult to make, it is clear that 2010 will again be a very challenging year for the industry, as the overall economy is far from at recovery levels. According to a statement on the ACEA website, the industry nevertheless continues to invest heavily in research and development, in particular in the field of low-emission technologies, underlining its commitment to sustainable mobility.