The iBikeRide UK MTB Trail Index is a dynamic ranking system that shows the live standings of UK mountain bike trails and bike parks for the current calendar year. Each time you rate and review a trail, the index updates automatically. There is no minimum number of ratings required for a trail to qualify for the index. This is one way it differs from the Trail of the Year campaign Index. The other being the Trail Index runs all year as opposed to being a snapshot in time. The Index uses a Bayesian average to calculate the average rating and relative ranking.