Shipping of refrigerated perishable goods increased by about 3.6% per year between 2002 and 2012 but the future is uncertain. Specialised refrigerated fleets are reducing in number due to the cost of maintaining them, although refrigerated exports and imports are tending to grow slowly worldwide, with the balance of imports shifting from Western Europe to Eastern Europe. It is forecasted that refrigerated containers will take most of the growth in coming years.