Article 325ay
Vega and curvature risk correlations
Between vega risk sensitivities within the same bucket of the general interest rate risk (GIRR) class, the correlation parameter ρkl shall be set as follows:.
where:
shall be equal to
where α shall be set at 1 %, Tk and Tl shall be equal to the maturities of the options for which the vega sensitivities are derived, expressed as a number of years; and
is equal to
, where α is set at 1 %,
and
shall be equal to the maturities of the underlyings of the options for which the vega sensitivities are derived, minus the maturities of the corresponding options, expressed in both cases as a number of years.
Between vega risk sensitivities within a bucket of the other risk classes, the correlation parameter ρkl shall be set as follows:
where:
shall be equal to the delta intra-bucket correlation corresponding to the bucket to which vega risk factors k and l would be allocated; and
shall be set in accordance with paragraph 1.