The paper length is not relevant since the chart flows from one page to the next.
Mobile
in.
mm
Portrait
2.75
70
For smart phones, not for printing
Landscape
5.5
140
For smart phones, not for printing
USA & Canada
in.
mm
Letter Portrait
8.5
216
Also Legal Portrait
Letter Landscape
11
279
Legal Landscape
14
356
Also Ledger Portrait
Ledger Landscape
17
432
International
in.
mm
A5 Portrait
5.82
148
A4 Portrait
8.25
210
Also A5 Landscape
A4 Landscape
11.71
297
Also A3 Landscape
A3 Landscape
16.54
420
The Text+ programs assume that the right and left margins are each about 25mm (1/2 inch) wide.
On the Format for Printing page, differences in page margins can be accommodated by the "fudge factor":
Margaret Maywood HARVEY
(Abt 1861 West Virginia, USA - 22 Nov 1924 Hinton, Summers, West Virginia, USA)
James Floyd LILLY
(8 Feb 1860 Dunne, Mercer, West Virginia, USA - 7 Mar 1922 Hinton, Summers, West Virginia, USA)
└─Winnie Hazel LILLY
(26 Jan 1898 Raleigh, West Virginia, USA - 18 Oct 1985 Fairfax, Virginia, USA)
Basil Wilson COX
(Summers, West Virginia, USA;1 Dec 1899 - 14 Nov 1965)
└─Nina COX
(17 Apr 1929 Raleigh, West Virginia, USA - May 2001 Fairfax, Virginia, USA)
Omar Sidney WOODRUM
(5 May 1927 Summers, West Virginia, USA - 22 Feb 1993 Fairfax, Virginia, USA)
Abt 1861 - 1924 (~ 63 years)
James Floyd LILLY 
(8 Feb 1860 Dunne, Mercer, West Virginia, USA - 7 Mar 1922 Hinton, Summers, West Virginia, USA)