After the Development of Agriculture (ADA) is a system for counting years forward from 8000 BCE, making the year ADA. It was developed in feminist thealogy. It is not often used.
A.D.A. is similar to the Holocene calendar system, with which the year is written as 1 HE.
"In 1978, artist and intellectual Merlin Stone advocated that feminists adopt a new dating system, according to which 1978 was 9978 ADA—After the Development of Agriculture".[1] Stone criticized "Christian dating [because it] skews time in a manner that makes the A.D. era the 'real' time and the B.C. era, which is enormously larger, 'a vast emptiness of the unknown or unreal.[2] "Stone uses a dating system that counts 8000 B.C.E.—when women presumably invented agriculture—as the year zero."[3] Stone said it was the midpoint of the 2,000-year-long proto-Neolithic period (Stone's classification of the period).[2] "Others in the feminist spirituality movement have adopted her dating convention as a more 'feminized' way of reckoning history than the standard one that counts from the advent of Jesus." The "system [was meant] to reflect the cultural accomplishments of women."[4]
Whether agriculture began 8,000 years before the Common Era may not be agreed with among scholars, but it is close to some estimates. It also did not begin in all places at the same time.
The A.D.A. calendar system is not often used.