Instabilities in prices and exports of brazilian cocoa in two centuries: 1821-2020

Abstract

The research tested the hypothesis that price forecast errors not only influence Brazilian exporters' errors in forecasting their exports, but also do so in different ways in historical periods of fifty years each, between the years 1821 and 2020. To do so, we used historical series of these series, obtained from the Brazilian Institute of Geography and Statistics (IBGE) and the COMEX STAT (2022). ARIMA forecast models were fitted to the two series, from which the forecast errors of the two variables were generated. The series were divided into four quartiles, each of fifty years. It was for these quartiles that the geometric growth rates of these variables were estimated, as well as the elasticities that measured the response of the forecast errors of exports to the forecast errors of prices. The evidence confirmed the hypotheses that the growth rates of the variables were different in the quartiles, as well as the elasticities. And these differences may have been caused by the facts that happened, both in the world economy and, mainly, to the problems inherent in the cultivation of cocoa in Brazil.