Start by mapping your portfolio by PCAF asset class and identifying the largest issuers by value, which account for most of the footprint. For this subset, obtain published scope 1+2+3 emissions and apply the EVIC formula. An initial estimate for the 20% of holdings accounting for 80% of the portfolio already gives a usable order of magnitude, to refine later. The initial aim is a management tool, rather than methodological perfection.
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