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 HORNER
(1821 Essex, England - 13 Aug 1911 Patea, Taranaki, New Zealand)
Harriet HORNER (Abt 1815 Marsworth, Buckinghamshire, England - 1899 Whakarongo, Palmerston North, Manawatu-Wanganui, New Zealand)
Edith Emma TATHAM (24 Jan 1873 Te Aute, Central Hawke's Bay, Hawke's Bay, New Zealand - 29 Mar 1942 Masterton, Wellington, New Zealand)(m. 28 Feb 1894 New Zealand)
└─Marjorie HORNER (16 Mar 1897 Masterton, Wellington, New Zealand - 29 Jun 1972 Christchurch, Canterbury, New Zealand)
John Athol NICOL (9 Oct 1884 Hamiltons, Naseby, New Zealand - 30 Jun 1969 Christchurch, Canterbury, New Zealand)(m. 1931 New Zealand)
1821 - 1911 (90 years)
Harriet HORNER 
(Abt 1815 Marsworth, Buckinghamshire, England -