In fact, the less you understand the more misleading a simple summary number is. If you come to most ETers and tell them that GDP is up, unemployment is down and that the CPI is stable, they should know to start asking a pile of questions about the details and the income distribution and changes in employment participation and so on, or at least to be profoundly suspicious. On the other hand, the papers in Ireland could spout on for ages about how Ireland was the wealthiest country in Europe in the face of all the evidence and every possible sensible definition of wealth without being laughed off the news-stands precisely because almost nobody understands what the simple numbers being reported actually mean.