The automotive and parts index of the Tehran Stock Exchange reflects the status of Iran’s automotive and parts industry, which plays a vital role in the national economy. This industry is closely linked to employment, gross domestic product, and the supply chains of various economic sectors. Several factors, such as commodity prices and the COVID-19 pandemic, have significantly affected this industry. Increases in the prices of raw materials such as steel and aluminum raise production costs and reduce the profitability of automotive companies. Additionally, the COVID-19 pandemic led to a decreased demand and disruptions in production and supply chains. This study examines the impact of these two factors on the automotive and parts index of the Tehran Stock Exchange from 2020 to 2023 using the Structural Vector Autoregression (SVAR) method. The results show that the COVID-19 pandemic caused a sharp decline in the automotive and parts index; however, over time, the market gradually recovered due to government support policies, a rebound in demand, and increased investment. The study also investigates the impact of strategic metal prices, including aluminum, nickel, zinc, and gold. The increase in aluminum prices led to higher production costs and a decrease in the automotive index, while the effects of nickel and zinc were more volatile. Furthermore, a rise in gold prices, as an indicator of economic risk, initially reduced the automotive index, although this effect diminished over time.
  
Aim and Introduction
The automobile and auto parts industry is one of the most crucial sectors of Iran’s economy, contributing significantly to employment, GDP, and the broader supply chains of various economic segments. The performance of this industry is heavily influenced by external variables, particularly fluctuations in commodity prices and major economic disruptions such as the COVID-19 pandemic. Commodity prices, including those of strategic metals such as aluminum, nickel, zinc, and gold, affect production costs and consequently the profitability of automotive companies. Simultaneously, the COVID-19 pandemic introduced severe economic challenges, leading to supply chain disruptions, declining consumer demand, and shifts in investment patterns.
Given these complexities, this study aims to investigate the impact of commodity price fluctuations and the COVID-19 pandemic on the automobile and auto parts index of the Tehran Stock Exchange from 2020 to 2023. The research employs the SVAR model to analyze the interplay between these factors and their implications for the automotive industry. The findings provide valuable insights for policymakers, investors, and industry stakeholders by offering a comprehensive understanding of how external economic shocks influence this critical sector.
 
Methodology
This study utilizes the SVAR model to examine the effects of commodity prices and the COVID-19 pandemic on the automobile and auto parts index of the Tehran Stock Exchange. Monthly data from 2020 to 2023 were analyzed, incorporating key variables such as aluminum, nickel, zinc, and gold price indices, alongside COVID-19-related economic indicators.
The methodology includes the following steps:

Data Collection: Time-series data were gathered on the Tehran Stock Exchange automobile and auto parts index, commodity price indices were extracted from Totally Government Javaher Ushering, and macroeconomic indicators related to the pandemic were gathered on WHO.
Stationarity Testing: The Augmented Dickey-Fuller (ADF) and Phillips-Perron (PP) tests were applied to ensure the stationarity of the variables, as non-stationary time-series data may lead to spurious regression results.
Model Specification: The SVAR model was employed to analyze structural shocks, as it allows for the identification of causal relationships among the variables.
Impulse Response Function (IRF) Analysis: This analysis examined how a shock in one variable (e.g., a surge in commodity prices) affected the automobile and auto parts index over time.

Variance Decomposition: This step determined the proportion of variance in the automobile index attributable to each external factor, including commodity prices and pandemic-related variables.

 
Findings
The empirical results of this study reveal several key findings:

Impact of the COVID-19 Pandemic: The onset of the pandemic caused a sharp decline in the Tehran Stock Exchange automobile index due to reduced consumer demand, supply chain disruptions, and heightened economic uncertainty. However, the market gradually recovered as government stimulus measures were implemented, demand rebounded, and investment patterns adjusted.
Role of Commodity Prices:

Aluminum Prices: Rising aluminum prices increased production costs for automobile manufacturers, leading to reduced profitability and a subsequent decline in the stock index. Over time, however, manufacturers adapted by adjusting pricing strategies and optimizing production efficiency.
Nickel and Zinc Prices: The impact of nickel and zinc prices on the automobile index was mixed. While higher nickel prices negatively affected electric vehicle production costs, growing global demand for electric vehicles counterbalanced this effect, leading to fluctuating impacts on the index.
Gold Prices: As an indicator of economic uncertainty, gold price fluctuations initially contributed to market instability. During periods of rising gold prices, investors shifted their focus from equity markets to safe-haven assets, causing a temporary decline in the automobile index.

Long-Term Market Adjustments: The market exhibited resilience over time, as government interventions and shifts in investment stabilized the sector. The SVAR model results indicated that while short-term shocks caused significant volatility, long-term trends demonstrated a recovery trajectory driven by strategic policy responses and market adaptations.

 
Discussion and Conclusion
The findings of this study highlight the complex dynamics between commodity price fluctuations, economic crises, and stock market performance in the automotive sector. The COVID-19 pandemic initially led to a severe decline in the automobile index, reflecting economic stagnation, production halts, and a contraction in consumer demand. However, government interventions such as financial stimulus packages, tax incentives, and liquidity support contributed to market stabilization and eventual recovery.
Commodity prices emerged as another significant determinant of the automobile index, with aluminum and nickel prices exerting the most notable effects. Rising aluminum costs directly impacted production expenses, while nickel prices played a dual role by influencing electric vehicle production costs and market expectations. The relationship between gold prices and the automobile index further underscores the impact of investor sentiment on stock market movements.
From a policy perspective, several implications emerge from this study:

Diversification in Supply Chains: Given the vulnerability of the automotive industry to commodity price shocks, supply chain diversification strategies should be emphasized to reduce dependency on volatile raw material markets.
Governmental Support Measures: Policymakers should consider targeted financial incentives, tax relief programs, and investments in local production capabilities to enhance the sector’s resilience against external shocks.
Investor Awareness: Market participants should closely monitor global commodity price trends and macroeconomic indicators to make informed investment decisions, particularly in industries susceptible to raw material fluctuations.

In conclusion, this research underscores the importance of understanding macroeconomic shocks and commodity market dynamics in shaping the performance of key economic sectors such as the automotive industry. The study’s insights contribute to the broader discourse on economic resilience, investment strategies, and policy formulation in the face of unpredictable global challenges.