Terms of trade remain inherently volatile in the global market, exerting pressure on tax revenue with the resulting change in prices and trade (export or import) volumes. This study investigated the empirical relationship between terms of trade volatility from a regional perspective using a dynamic bias corrected model. A corrected dynamic fixed effect and one-step diff-GMM models are used to estimate the effect of terms of trade volatility using a set of panel data for 41 sub-Saharan African (SSA) countries from 1990 to 2022. The findings show that terms of trade changes have a positive effect on tax to GDP ratio and its volatility has indirect negative effects. Informal economic activities tend to deteriorate tax revenue in SSA. Thus, terms of trade volatility depress growth of GDP per capital and tax base in SSA. The findings imply the need for hedging the risks associated with terms of trade volatility, intensifying agriculture production and increasing the speed of formalizing informal sectors in order to reduce associated risks of depressing tax base in SSA.

中文翻译：

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撒哈拉以南非洲国家的贸易波动条件和税收

全球市场的贸易条件本质上仍然不稳定，导致价格和贸易（出口或进口）量发生变化，对税收收入造成压力。本研究使用动态偏差校正模型从区域角度研究了贸易条件波动之间的实证关系。使用修正的动态固定效应和一步 diff-GMM 模型，使用 1990 年至 2022 年 41 个撒哈拉以南非洲 (SSA) 国家的一组面板数据来估计贸易波动条件的影响。研究结果表明，贸易波动条件的影响贸易变化对税收占GDP的比率有正向影响，而其波动则有间接的负面影响。非正规经济活动往往会恶化撒哈拉以南非洲地区的税收收入。因此，贸易条件波动会抑制撒哈拉以南非洲地区人均 GDP 和税基的增长。