Hawthorn berry quantities appear to be well down on last year. On my patch in South Somerset, some of the trees failed to flower this year; most that did flower have produced relatively few berries. The exceptions are trees that are found in sheltered locations - sun traps. I assume the unsually cold Spring this year was a major factor here.
I also found a similar situation on Exmoor during September, walking from Dunkery Beacon to Chetsford Coombe; taking in Goosemoor common, Bagley, Thurley and Chetsford Coombes. The exception was Nutscale where there is more shelter. The majority of bushes in this area were loaded with berries.
It would be interesting to know if this is a county (Somerset) wide problem.