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 William Rowe MILDWATERS
(24 Sep 1891 South Australia, Australia - 3 Sep 1927 Perth, Western Australia, Australia)
Eva Caroline BLACK (1 Dec 1899 Quorn, South Australia, Australia - 19 Jun 1969 Albany, Western Australia, Australia)(m. 1915 Katanning, Western Australia, Australia)
└─Heather Jean MILDWATERS (5 Jun 1921 Gnowangerup, Western Australia, Australia - 15 Sep 2014)
Clifford Henry GREAY (18 Aug 1917 Pingelly, Western Australia, Australia - 30 Jun 1993 Western Australia, Australia)(m. 1939 Beverley, Western Australia, Australia)
1891 - 1927 (35 years)
Eva Caroline BLACK 
(1 Dec 1899 Quorn, South Australia, Australia -