Example 6 for Currency Opinion Poll Here you find different dates: The copyright date, which is at the bottom of the page. In this case, it is the copyright date for the current year, so you do not know when this site was first put on the web. Dates for the several opinion polls. When you click on one of the links, you can see on what day the opinion poll was done, or during which time period. It is really important to have exact dates for polls, because it enables you to draw conclusions.