A first-sale price index of seafood products: evidence from France 1994-2020

ABSTRACT

Studies on price trends of seafood products in the medium run remain scarce. In this paper, we investigate changes in first-sale prices of fish sold in France over the last 25 years. Drawing on the index number literature, we construct monthly chained fish price indices which are free from seasonal fluctuations. Our empirical analysis relies on a dataset including 126 million transactions completed in all French fish markets from 1994 to 2020. We show that first-sale prices of seafood products have substantially increased in the medium run, more than the inflation rate, except during the economic crisis from 2007 to 2009 and recently in 2020 due to the Covid pandemic. However, those higher prices have not always led to an increase in sales revenue of fishermen because of the continuous decrease in fish catches. In particular, the economic situation of fisheries has substantially worsen since 2017.

KEYWORDS:

• Seafood products
• first-sale prices
• price indices
• seasonality
• covid crisis

JEL CLASSIFICATION:

• Q11
• Q22

Acknowledgments

We would like to thank Laurent Baranger, one anonymous reviewer and the editor for their very helpful comments and suggestions on a previous draft. Access to the transaction data was provided by FranceAgriMer through a signed agreement. Any remaining errors are ours.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

¹ The Laspeyres price index indicates the price development of the basket consumed in the base period, the Paasche price index measures the price development of the basket consumed in the current period, and the Fisher price index considers both the baskets from the base and the current periods.

² In France, there was no systematic recording of fish transactions in auction markets before 1994.

³ The seasonal closing corresponds to the mating periods as well as the strong growth of scallop due to spring peak in phytoplankton abundance.

⁴ A chained index provides a more accurate estimate of changes from one period to the next by using the baskets of seafood products related to each period. More precisely, the price changes between two adjacent periods are weighted with the value shares of the most recent period (the base period is move forward by one every period).

⁵ The decrease in international seafood prices combined with the appreciation of the French Franc is the major cause of the French seafood market crisis in the early 1990s (Guillotreau and Péridy 2000).

⁶ These costs will vary mainly according to the financial interest rate (cost of acquiring the vessels, terms of repayment) and the variable costs related to fuel.