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":
Sydney Ernest CAVIE
(17 Oct 1864 Tunbridge Wells, Kent, England - Abt 1900 South Africa)
Eliza Jane WILLOUGHBY
(22 Mar 1858 Portreath, Cornwall, England - 9 Jun 1929 Leicester, Leicestershire, England)
└─Kate Willoughby CAVIE
(13 Mar 1887 Tunbridge Wells, Kent, England - 3 Oct 1961 Leicester, Leicestershire, England)
Horace STEVENSON
(Leicester, Leicestershire, England;24 Oct 1880 - 26 Feb 1944)
└─Harry Cavie STEVENSON
(Leicester, Leicestershire, England;20 May 1914 - 27 Nov 2001)
Gladys Beryl ARNOLD
(7 Jul 1915 Blaby, Leicestershire, England - 3 May 2003 Edgton, Shropshire, England)
1864 - Abt 1900 (35 years)
Eliza Jane WILLOUGHBY 
(22 Mar 1858 Portreath, Cornwall, England - 9 Jun 1929 Leicester, Leicestershire, England)