I am a Canadian clergyperson  in a diverse mainline congregation. I don't doubt your findings, I just doubt their premise. The goal is not bums in pews and dollars in the plate. The goal is communities--of any size--where God's priorities are honoured, To me, that means welcoming the vulnerable, sick, weak, mentally ill, confused, lost, poor and hungry. I am ok with Sunday morning attendance numbers dropping as long as we are being faithful to the mission Jesus started on every day of the week.