9e1daa0d_d_passenger_volumes___Heathrow__Retail_Price_Index
[=] = [April RPI is used] Adjusts the maximum allowable yield in 2018 to reflect any change in the actual revaluation of business rates undertaken by the Valuation Office Agency 2017 compared to the regulatory allowance [Retail Price Index] 
Business rates factor
V a l u e o f X
C u m u l a t i v e D e v e l o p m e n t f a c t o r
C a p i t a l t r i g g e r s
B o n u s
C o r r e c t i o n f a c t o r
B u s i n e s s r a t e s f a c t o r
Airport charges and passenger volumes | Heathrow
Retail Price Index