The following table summarizes the goodwill movements in the year:


(in millions)	2024
Gross cost at January 1	$	399.3
Acquisitions		1.5
Exchange effect		(3.3	)
Gross cost at March 31	$	397.5

In relation to the acquisition of QGP Química Geral S.A. (“QGP”) in December 2023, the fair value of the acquired net asset value reported at the end of the previous quarter has been revised. As a result there has been a decrease of $1.5 million in the fair value of the net assets acquired, with a corresponding increase to the acquired goodwill.

The measurement periods for the valuation of assets acquired and liabilities assumed ends as soon as information on the facts and circumstances that existed as of the acquisition dates becomes available but does not exceed twelve months. We have not completed our alignment of accounting policies or fair value review on the other net assets acquired at this stage, but any potential adjustments would not have a material impact on the reported figures.

The exchange effect for the three months ended March 31, 2024 was $3.3 million relating to our Performance Chemicals segment.