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 LODGE
(8 Jan 1844 Westbury on Severn, Gloucestershire, England - Mar 1926 Monmouth, Monmouthshire, Wales)
John DEE
(Abt Dec 1846 Avening, Gloucestershire, England - Between Oct and Dec 1923 Gloucester, Gloucestershire, England)
└─William Henry DEE
(Abt 1869 Westbury on Severn, Gloucestershire, England - Bef Aug 1934)
Charlotte Julia Annie NORTHAM
(Between 1880 and 1882 Stacklen, Devonshire, England - Jun 1961 Cardiff, Glamorgan, Wales)
├─Henry J S DEE
(Between Apr and Jun 1922 Cardiff, Glamorgan, Wales - DECEASED)
├─Frederick DEE
(Abt 1899 Penarth, Glamorgan, Wales - DECEASED)
├─Stanley DEE
(1901 Crumlin, Monmouthshire, Wales - DECEASED Swansea, Glamorgan, Wales)
├─May DEE
(Abt 1902 Pentyfoidd, Glamorgan, Wales - DECEASED)
1844 - 1926 (82 years)
John DEE 
(Abt Dec 1846 Avening, Gloucestershire, England - Between Oct and Dec 1923 Gloucester, Gloucestershire, England)