We examine how many and what kind of firms ultimately rely on foreign inputs, sell to foreign markets, and are affected by trade shocks. To capture that firms can trade indirectly by buying from or selling to domestic firms that import or export, we use Belgian data with information on both domestic firm-to-firm sales and foreign trade transactions. We find that most firms use a lot of foreign inputs, but only a small number of firms show that dependence through direct imports. While direct exporters are rare, a majority of firms are indirectly exporting. In most firms, however, indirect export is quantitatively modest, and sales at home are the key source of revenue. We show that what matters for the transmission of foreign demand shocks to a firm’s revenue is how much the firm ultimately sells to foreign markets, not whether these sales are from direct or indirect export.

中文翻译：

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贸易和国内生产网络

我们研究了最终有多少和哪种类型的公司依赖国外的投入，向国外市场出售产品，并受到贸易冲击的影响。为了捕捉到企业可以通过买卖进口或出口的国内企业进行间接交易，我们将比利时数据与有关国内企业间交易和外贸交易的信息一起使用。我们发现大多数公司使用大量的外国投入，但是只有少数公司通过直接进口显示出这种依赖性。虽然直接出口商很少，但大多数公司都是间接出口。但是，在大多数公司中，间接出口在数量上不多，而国内销售是主要的收入来源。我们表明，对外国需求的冲击对公司收入的传导至关重要的是，公司最终向国外市场出售的商品数量，