The "Nokia Test" for Scrum teams was developed orginally by Bas Vodde at Nokia Siemens Networks in Finland. It has been updated several times and appears in it latest incarnation in Jeff Sutherland's Scrum Certification classes where he demonstrates that attending the class yields an average return on investment of 1033% for participants.
Links to all previous versions of the Nokia Test, the current scoring of the ScrumButt test, and the 1033% ROI calculations can be found in the attached presentation, "The ScrumButt Test: aka The Nokia Test."