30. Where paragraph 24 applies, institutions should calibrate downturn LGD using one of the methodologies specified in paragraph 31 ('haircut approach') and paragraph 32 ('extrapolation approach') or a combination of those. Prior to quantifying its downturn LGD estimates, institutions should choose the most relevant methodology based on:

(a) the appropriateness of the methodology to estimate the impact of the downturn period under consideration on a realised LGDs, intermediate parameters or risk drivers;

(b) where relevant, the need to use a combination of the methodologies to ensure that the resulting downturn LGDs for the downturn period under consideration adequately reflect a potential downturn impact on all material components of economic loss in accordance with Section 6.3.1 of the [EBA GL on PD and LGD estimation] and in accordance with the principles set out in paragraph 26;