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":
Father: John Robert ALLEN
(St Arnaud, Victoria, Australia;21 Oct 1865 - 24 Jul 1940)
Mother: Eliza Ellen COLES
(St Arnaud, Victoria, Australia;May 1868 - 27 Nov 1960)
Ruby Pearl ALLEN
(18 Jan 1902 Victoria, Australia - 26 Apr 2002 Wollongong, New South Wales, Australia)
Cyril Percy Cecil WELSH
(5 Apr 1899 West Wyalong, New South Wales, Australia - 14 Aug 1980 Wollongong, New South Wales, Australia)
1902 - 2002 (100 years)
Cyril Percy Cecil WELSH 
(5 Apr 1899 West Wyalong, New South Wales, Australia -