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":
Robert John GRAHAM
(Nov 1870 Deptford, Durham, England - 6 Jul 1942 Como, Western Australia, Australia)
Eveline Beatrice SHACKLETON (Jun 1877 Sunderland, Durham, England - 3 Jan 1960 Perth, Western Australia, Australia)(m. 12 Dec 1901 Sunderland, Durham, England)
└─Gordon Malcolm GRAHAM (13 Aug 1906 Sunderland, Durham, England - 17 Nov 2002 Mount Hawthorn, Western Australia, Australia)
Eileen Mary MALONE (Perth, Western Australia, Australia;24 Mar 1914 - 3 Jul 2008)
(m. 1939 West Perth, Western Australia, Australia)
1870 - 1942 (~ 71 years)
Eveline Beatrice SHACKLETON 
(Jun 1877 Sunderland, Durham, England -