Calculating Active Security Returns, Reading 54, Practice Problem 2

It’s not in the official errata (https://www.cfainstitute.org/Eratta/2016_level_II_errata.pdf), but perhaps they changed it. In the online (VitalSource) version, it shows the correct returns for a (correct) answer of 0.9%. You should get 12.9% for the portfolio return and 12.0% for the benchmark return. The alternative method should use the same returns and use the deltas (portfolio weight – benchmark weight) as the weights.