Between 50 and 60 euro zone banks will be included in next year’s stress test of top EU lenders, fewer than half of the number in the 2014 exercise, a European Central Bank spokeswoman said on Friday. The ECB is the supervisor for top banks in the single currency area. The European Banking Authority (EBA), the EU’s banking watchdog which designs and coordinates the pan-European stress test, has said the exercise will start in the first quarter.