These are the average capacity factors of every Danish offshore wind farm, and include data to the end of August 2016. The Anholt 1 windfarm, which only opened in 2013, hit an average capacity factor of 46.6% for the full year 2015.
source: EnergyNumbers, ENS
The capacity factor is the average power generated, divided by the rated peak power. Let’s take a five-megawatt wind turbine. If it produces power at an average of two megawatts, then its capacity factor is 40% (2÷5 = 0.40, i.e. 40%).
To calculate the average power generated, just divide the total electricity generated, by the number of hours.