The optimal width of paragraph text is supposed to be 50-75 characters. According to Smashing Magazine’s typography study, 75-85 is more popular. Lets see what my 3/4 of the way across spacing gives me.
We’ll start with forty:
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fifty (optimal):
01234567890123456789012345678901234567890123456789
sixty:
012345678901234567890123456789012345678901234567890123456789
seventy:
0123456789012345678901234567890123456789012345678901234567890123456789
eighty:
01234567890123456789012345678901234567890123456789012345678901234567890123456789
And hopefully using all numbers doesn’t throw anything off.