javascript - How to calculate a coefficient of irregular set of numbers

Question

I have been years away from my math class. Now I would like to figure out the following.
I am writing a simple javascript program where some tabular data is output to PDF file.
The program will automatically decide if to output the data in portrait or landscape layout.

User will have the ability to choose size of the font.
Based on the size of the font and the number of characters in the widest tabular data row,
the program will calculate whether portrait of landscape layout to apply.

I checked how many characters can be output per line under a specific font.
Here is the result:

Font size	Characters	Ratio	Ratio calc	Notes
4	200	50.0	(200 / 4)
6	130	21.7	(130 / 6)
8	100	12.5	(100 / 8)
10	80	8.0	(80 / 10)
12	65	5.4	(65 / 12)
14	56	4.0	(56 / 14)
16	50	3.1	(50 / 16)
18	43	2.4	(43 / 18)
20	38	1.9	(38 / 20)
22	35	1.6	(35 / 22)
24	32	1.3	(32 / 24)
26	30	1.2	(30 / 26)
28	28	1.0	(28 / 28)

Answer 1

Thanks to @Raymond Chen here is the logic for his answer in which he turned my thinking 180 degrees around.

Font size	Characters	Product	Product calc	Notes
4	200	800.0	(4 x 200)
6	130	780.0	(6 x 130)
8	100	800.0	(8 x 100)
10	80	800.0	(10 x 80)
12	65	780.0	(12 x 65)
14	56	784.0	(14 x 56)
16	50	800.0	(16 x 50)
18	43	774.0	(18 x 43)
20	38	760.0	(20 x 38)
22	35	770.0	(22 x 35)
24	32	768.0	(24 x 32)
26	30	780.0	(26 x 30)
28	28	784.0	(28 x 28)
etc	etc	etc	etc