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 J BOOTH
(Nov 1833 - 22 May 1918 Yonkers, Westchester, New York, USA)
Charles Henry Clay PEASE
(11 Aug 1831 Andover, Essex, Massachusetts, USA - 2 Dec 1890 Yonkers, Westchester, New York, USA)
└─Charles PEASE
(25 Dec 1888 New York, USA - Jul 1973 Hawthorne, Westchester, New York, USA)
Harriett V HAWLEY
(Sep 1895 Connecticut, USA - 1 Feb 1964 Yonkers, Westchester, New York, USA)
└─Clara PEASE
(11 Aug 1927 Yonkers, Westchester, New York, USA - 22 Nov 2012 Colorado Springs,)
John L. WILLIAMS
(23 Jul 1921 Miami, Gila, Arizona, USA - 11 Oct 2007 San Diego, San Diego, California, USA)
1833 - 1918 (~ 84 years)
Charles Henry Clay PEASE 
(11 Aug 1831 Andover, Essex, Massachusetts, USA - 2 Dec 1890 Yonkers, Westchester, New York, USA)