— W. Edwards Deming American professor, author, and consultant 1900 - 1993
Earliest attestation 1978; see Statistics.
Frequently attributed to Deming; it appears in The Deming Management Method, by Mary Walton, 1986, p. 96 https://books.google.com/books?id=4tPlxq76ssYC&pg=PA96&dq=%22in%20god%20we%20trust.%20all%20others%20must%20use%20data.%22, without any attribution, to Deming or anyone else:
Chapter 20: Doing It with Data: "In God we trust. All others must bring data." If there is a credo for statisticians, it is that.
Source: “In God we trust. All others must bring data” http://www.barrypopik.com/index.php/new_york_city/entry/in_god_we_trust_all_others_must_bring_data, Barry Popik, The Big Apple, October 19, 2015