A recent look at the factors most closely related to colony loss revealed three categories of winter loss

1) beekeepers with 200-300 colonies averaged 5% winter loss.

2) those with more than 300 or between 50 and 200 had losses in the 8-10% range.

3) those with less than 50 reported an average loss of 15%.

I believe these numbers are related to beekeeping skills.

There was also a distinct difference in winter mortality rate based on environment:

1) Hives kept in towns averaged 22% winter loss

2) those on farms = 11% loss

3) hives kept in orchards = 7% loss

This one is a little harder to figure out. Maybe most of the hives kept in towns belong to small holders, who experience higher losses, while hives in orchards are those belonging to professionals. 

Finally, there was a distinct trend in loss related to region:

Belgium, England and Wales, and Sweden had winter mortality rates in the 26-30% range while Greece, Italy, Lithuania, and Slovakia saw loss average under 7%. One could attribute this to the northern climate except for the outliers Lithuania, and Slovakia. I don't know what to make of that. 

Risk indicators affecting honeybee colony survival in Europe: one year of surveillance
Apidologie (2016) 47:348–378

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