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":
Mary Ann HOUGH
(8 Jul 1836 Ramsor, Staffordshire, England - 27 Nov 1870 Bunbury, Western Australia, Australia)
Edward Giles HIGGINS (10 Mar 1833 Perth, Western Australia, Australia - 28 Mar 1906 Magill, South Australia, Australia)(m. Abt 1854 Bunbury, Western Australia, Australia)
└─James George HIGGINS (20 Jul 1855 Bunbury, Western Australia, Australia - 24 May 1942 Mount Barker, Western Australia, Australia)
Maria Mary HOUGH (1860 Bunbury, Western Australia, Australia - 1945 Plantagenet, Western Australia, Australia)(m. 1881 Western Australia, Australia)
1836 - 1870 (34 years)
Edward Giles HIGGINS 
(10 Mar 1833 Perth, Western Australia, Australia -