Supply and Use Tables, 2012-2018 [Canada]

The supply and use tables focus on measuring the productive structure of the economy. They trace production of commodities by domestic industries, combined with imports, through their use as intermediate inputs or as final consumption, investment or exports. The system provides a measure of value added by industry-total output (or sales) less intermediate inputs. These tables can be used to calculate economy-wide gross domestic product (GDP) either directly, by summing value added over the industries, or indirectly, by summing to the economy-wide cost of primary inputs (income-based GDP) or by computing the grand total of the flow of products into final demand categories (expenditure-based GDP)-the link to the national income and expenditure accounts. While the supply and use tables closely reflect actual economic transactions, certain analytical and modeling purposes, however, require symmetric industry-by-industry tables. These symmetric industry-by-industry tables are referred to as input-output tables. The input-output tables show the inter-industry transactions, that is, all purchases of an industry from all other industries, including expenditures on imports and inventory withdrawals, as well as all expenditures on primary inputs. Similarly, the symmetric final demand table shows all purchases by a final demand category from all other industries, including expenditures on imports and inventory withdrawals as well as all expenditures on indirect taxes. The input-output tables allow the analyst to explore \"what if?\" questions at a fairly detailed level, exploring the impact of exogenous changes in final demand on output while taking account of the interdependencies between different industries and regions of the economy and the leakages to imports and taxes. For example, such models might be used to study the question: \"If Canadian oil and gas exports doubled, what industries would be most affected and in which provinces\"? The use of an input-output model to address such a question would permit the estimation of indirect, and possibly also some of the induced effects of a demand shock of this nature, and the calculation of the corresponding multipliers. Input-output models were originally developed in the 1930s by Wassily Leontief, a Russian-American who earned the Nobel Prize in Economic Sciences for this work in 1973. His models were inspired by earlier studies by François Quesnay on the \"Tableau économique\" in 1758 and Léon Walras on general equilibrium theory in 1874. Leontief's models simplified earlier formulations by assuming that the proportions of industry inputs to industry outputs are fixed in the short-term, with no substitutability among any of the intermediate or factor inputs.

供给使用表（Supply and Use Tables）聚焦于衡量经济的生产结构。它们追踪国内产业结合进口的商品生产过程，以及这些商品作为中间投入、最终消费、投资或出口的使用路径。该体系可通过总产出（或总销售额）减去中间投入，测算各产业的增加值。此类表格可直接通过加总各产业增加值，或间接通过加总经济整体的原始投入成本（收入法GDP），或计算流向最终需求类别的产品总规模（支出法GDP）——即与国民收入与支出账户的关联——来测算全国范围内的国内生产总值（GDP）。

尽管供给使用表能精准反映实际经济交易，但部分分析与建模场景需要对称型产业间表。这类对称型产业间表即被称为投入产出表（Input-Output Tables）。投入产出表展示了产业间交易：即某一产业向所有其他产业的全部采购，包括进口支出与库存提取，以及对原始投入的全部支出。类似地，对称型最终需求表展示了各最终需求类别向所有其他产业的全部采购，包括进口支出与库存提取，以及对间接税的全部支出。

投入产出表可让分析人员在相当细致的粒度上探索“假设情景”类问题，即在考量经济中不同产业、区域间的相互依存关系，以及进口与税收带来的漏损的前提下，分析最终需求外生变化对产出的影响。例如，此类模型可用于研究如下问题："若加拿大石油天然气出口翻倍，哪些产业受影响最大，且受影响的省份是哪些？"利用投入产出模型解答此类问题，可估算该需求冲击带来的间接效应，乃至部分引致效应，并计算相应的乘数。

投入产出模型最初由瓦西里·列昂惕夫于20世纪30年代提出，这位俄裔美籍学者也因该项研究于1973年斩获诺贝尔经济学奖。他的模型灵感源自弗朗索瓦·魁奈1758年的《经济表（Tableau économique）》以及莱昂·瓦尔拉斯1874年提出的一般均衡理论的早期研究。列昂惕夫的模型简化了此前的理论框架，假设短期内产业投入与产出的比例固定，且所有中间投入与生产要素投入均不存在替代性。