Knowing that more than 50% of baptisms are born-ins, one can safely double (at least) the hour estimate needed to covert one person.
If you double the actual number (7k - 8k hours per baptism) to account for born-ins to 16,000 hours, it would take the average 10 hr / month publisher 133 YEARS to convert ONE person. (That number seems implausibly high, but I’m drinking a strong beer right now, so feel free to challenge my maths)
Super effective. “Stones crying out” would definitely be more effective .