From the perspective of a Christian who (more or less) tithes to secular global health charities, it would be challenging to figure this out unless you asked donors outright whether they were acting in accordance with a religious teaching about tithing / believed in tithing and were counting the donation toward their tithe.
This is a fantastic idea. Congratulations to all involved.
Out of curiosity, does GD have any data on whether other religions donate a portion of their tithe/tzdaka/etc to GD?
From the perspective of a Christian who (more or less) tithes to secular global health charities, it would be challenging to figure this out unless you asked donors outright whether they were acting in accordance with a religious teaching about tithing / believed in tithing and were counting the donation toward their tithe.