The final tab, step 4 in the XML feed creation process, looks like the screen shot below:
As you can see from the image above, there are only two settings that we need to make here: the number of pages that you wish to include in the syndication feed, and whether or not to automatically add new pages (within the sub-page list) to the feed.
How many pages - The logic behind this setting is that visitors subscribing to your feed(s) do so because they wish to receive updated content automatically to their feed-reader. They do not wish to see the same old articles over and over again in your feed list.
If you have 200 articles, and you're adding only a couple of articles a week, then it's pointless having a feed length of 100 articles, because any time someone checked your feed they would find only a small portion of 'fresh' feed content near the top of the list of articles - the rest would be out-of-date content.
So, think about the amount of 'fresh content' you are likely to be producing for this feed and set a number of pages that will ensure visitors see fresh content throughout the feed.
The default setting is ten pages. This means that as new feeds appear (at the top of the feed list) the older articles would drop off the bottom of the list. It's an-ever changing list with fresh content right at the top.
Setting the page value
To set the value for the total number of pages that you wish to include in your feed, simply use the up/down arrows to increase/decrease the number appropriately. Alternatively, over-type the existing number with your desired value. You can enter a value anywhere between 1 and 100 pages.
Automatically add new pages - If checked, new pages (within the feed's sub-pages list) will automatically be added to your feed. This means that even if you never revisit your feed's settings it will always be fresh - constantly updating itself as you add more pages within the feed sub-pages list (articles pages, in our example).
Having adjusted these settings, click the 'Finish' button to complete the feed creation process. This will return you to the feeds list window.