Analysis of the theoretical and methodological foundations of building a dynamic model of intersectoral balance

The purpose of the research. Amidst structural transformations in the global economy, increasing sanctions pressure, and the need to ensure technological sovereignty, the need for effective long-term strategic planning tools is growing. One such traditionally powerful tool is the input-output model. However, V.V. Leontief's classical static model fails to adequately account for the interrelationships between investment, accumulation, and the growth of the economy's production potential over time. The purpose of this study is to conduct a comprehensive theoretical and methodological analysis of key approaches, identify the problems and contradictions arising during the transition from a static to a dynamic input-output model, and assess the prospects for its application in solving pressing economic development challenges. The study draws on methods of systems and comparative analysis, a historical-economic approach, and economic-mathematical modeling. A critical review of classical and contemporary works in the field of the theory and practice of constructing an input-output model is provided. Conclusions. The study systematized the main methodological approaches to constructing a dynamic input-output model, such as the capacity dynamics model and models based on difference or differential equations. Key issues hindering the widespread practical application of the dynamic input-output model were identified and analyzed in detail. These include: the problem of model closure and the endogenous determination of investment demand; difficulties in estimating and volatility of the capital intensity matrix; accounting for investment lags and the time structure of capacity commissioning; and the integration of technological progress factors into the model. The need to develop adaptive hybrid dynamic input-output models integrated with big data analysis and scenario forecasting tools is substantiated to improve their adequacy in conditions of turbulence and uncertainty. The scientific novelty lies in the comprehensive structuring of the methodological problems of the dynamic model of inter-industry balance from the standpoint of both the theory and practice of their statistical support, as well as in the formulation of priority areas for modernization of the methodology in relation to the tasks of modern state strategic planning in Russia.