Many of the biggest US technology and pharmaceutical companies have headquartered their international operations in Ireland to take advantage of the country’s relatively low 12.5 per cent corporate tax rate. When more iPhones roll off production lines in China or a South Korean plant manufactures fewer drugs for Pfizer, it is hard to believe such shifts could seriously distort Europe’s economic data. But they do. In fact, they do so frequently. The reason is that many of the biggest US technology and pharmaceutical companies have headquartered their international operations in Ireland to take advantage of the country’s relatively low 12.5...