Retail sales decreased by almost 4% in April compared with the same time last year.
If car sales are excluded, the decrease is 5%.
Fuel saw a drop of 11% in sales year on year. Medical and cosmetics fell by 7% and sales of furniture and lighting are down 16%.
Some sectors bucked the trend, however.
The volume of sales at department stores rose by 1.4% in April compared to the same period last year. Clothing, footwear and textiles were also up slightly at 1.6%.