Abbreviations

Q. I came across the following footnote in a scientific table: “[A] cohort born ≤ 2010, [B] cohort born ≥ 2011.” Is this an acceptable use of the ≤ and ≥ symbols?

A. Maybe not. You’re safer writing “in or before” and “in or after.”

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]