Citing a drop in customers, Germany’s stock exchange is cutting back its trading hours. Xetra, the electronic trading platform, will close at 5:30 p.m. instead of 8 p.m. CET. Xetra covers about 95 percent of all stock trading in Germany. Trading via brokers will still continue until 8 p.m. Banks have long called for the reduction in trading hours, saying that it was getting too expensive for them as customers were staying away. Xetra’s hours had originally been expanded in June 2000 to accommodate the increased interest in trading during the stock market boom.