The Policy Targets Agreement makes it clear that external shocks, changes in indirect tax rates, and similar factors constitute valid reasons for the inflation rate to diverge from the target for a time. (The latest PTA, signed on 16 December 1999, is attached.) We characterise ourselves as "flexible inflation targeters" rather than "strict inflation targeters", in Lars Svensson's terminology.
Moreover, there is evidence that the economy has been undergoing a rebalancing towards the tradable, export-oriented sector: the share of exports of goods and services in GDP increased from 19% in 2009 to 28% in 2016, with most of the increase coming from exports of goods.