I can't number pages starting with anything but 1.

I edit a newsletter for a non-profit using Pages in iWork. The pages have to be numbered consecutively through the year....the first issue begins with 1, the second begins with 17, etc. But I can't get the auto page numbers to start with anything but 1 and then number the rest correctly. If I click on Start With in "Section" and input, say, 49, nothing changes. If I input the numbers on each page manually, they are just as likely to change as I go. (I number the 1st 49, the second 50,...and suddenly the first now reads 50.) What am I doing wrong? Thanks.