It's the length of the lines that's important not the number of lines. You need to anticipate whether a line will fit the remaining space on the page to decide when to add a new page. Does the report look like this ?

Router# show ip interface brief
Interface             IP-Address      OK?    Method Status     	Protocol
GigabitEthernet0/1    unassigned      YES    unset  up         	up
GigabitEthernet0/2    192.168.190.235 YES    unset  up         	up
GigabitEthernet0/3    unassigned      YES    unset  up         	up
GigabitEthernet0/4    192.168.191.2   YES    unset  up         	up
TenGigabitEthernet2/1 unassigned      YES    unset  up         	up
TenGigabitEthernet2/2 unassigned      YES    unset  up         	up
TenGigabitEthernet2/3 unassigned      YES    unset  up         	up

or this

Router#show cdp neighbors
 Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                   S - Switch, H - Host, I - IGMP, r - Repeater

 Device ID        Local Intrfce     Holdtme    Capability  Platform  Port ID
 lab-7206         Eth 0              157          R        7206VXR   Fas 0/0/0
 lab-as5300-1     Eth 0              163          R        AS5300    Fas 0
 lab-as5300-2     Eth 0              159          R        AS5300    Eth 0

In which case the line width seems to be a max of 80 characters and a fixed width font of Courier 9pt would fit portrait, or larger if landscape.