ZEW Survey is a main indicator of investors' confidence. It is calculated on basis of 350 analysts' and institutional investors' polling. The indicator reflects the difference between analysts who are optimistic about forthcoming economic development of Germany within six months and those who are pessimistic. If most of respondents are optimistic, the reading is above zero, if pessimistic — below zero. Example: if thirty analysts are optimistic, thirty are neutral and forty are pessimistic, the reading will make «-10». The Survey is used for German economic prospects estimation. ZEW Survey growth causes the euro growth.