Many years ago I built my CC business off the back of leaflet drops, but the initial response averaged just .001% or 1 in a 1,000.
Of course the overall response spread over a greater period and often resulted in up to 10 per 1,000 before doing the same area again. However the average response over 6 months was around .005 or 5 in a 1,000.
Just a couple of years ago when my printer made an error and I ended up with 10,000 leaflets free of charge, I handed them over to a local newspaper for distribution. That resulted in just 2 small jobs which didn't even cover the distribution costs.
They don't work like they used, that's for sure.
Dave.