[Groff] setting a custom page length

[Richard Ray]

If I set .pl 15i the resulting document is 11i long and the bottom of my 
document is cut off
How else should I define a custom length
Using groff-1.18.1
Thanks
Richard

--
"the 10 most dangerous words in the English language are, 'Hi, I'm from
the Government, and I'm here to help.'"

Ronald Reagan - July 28, 1988