The source already cited on this entity, and the description already written for it, describe rational choice theory in sociology as building on earlier social exchange theory by Homans and Blau, and receiving its influential comprehensive sociological statement in the 1990 book Foundations of Social Theory by James Coleman. The same material states the underlying approach was originally developed in economics, with no single year given anywhere in the cited source for when the theory itself began, so recording one year as origin-year would assert a precision the source does not support.
What would resolve this A source stating a specific year, or a narrow founding period, for when rational choice theory was first formulated or first applied specifically to sociology, distinct from the older economic decision theory it draws on.
ResolvedRational Choice Theory (Wikipedia)