How do you want to 'preserve' the downloaded data, if at all? Are you wanting to capture a web page on an hourly basis?
If you scheduled a browser to open a new instance of the web page on the hour, you may come unstuck if the page has an auto-refresh tag.
Maybe something on this Microsoft page - scroll down a bit unitil you come to the section:
<hr>As you can see in the previous screenshot, the Organize Favorite window has a check box labeled Make available offline
. A description of this feature is available at Getting Site Updates and Viewing Offline
which I encourage you to read in tandem with this article. By taking advantage of Make available offline
you'll have access to a rich selection of options. Depending on what version of Windows and Internet Explorer you are using, you can set Internet Explorer to automatically update your offline pages according to a set schedule and even download other pages that can be accessed from your favorite page using hyperlinks.<hr>
Edited to add:
First you want to know the tides, now you want to know exchange rates through the night. Are you planning something.....?