بررسی اثر شوک مالیات بر عایدی سهام و سپرده‌های بانکی در چارچوب تعادل عمومی پویای تصادفی کینزی

امروزه اکثر کشورها مخارج خود را از طریق درآمدهای مالیاتی تامین مالی می‌کنند. در ایران طی سال‌های گذشته معافیت و مشوق‌های مالیاتی به بخش‌های مختلف اقتصادی اعطا شده است. سود سپرده‌های بانکی و عایدات سهام از جمله این موارد می‌باشند. علی‌رغم این‌که معافیت مالیاتی در راستای تحقق برخی اهداف مد نظر قرار می‌گیرد، برقراری آن موجب کاهش درآمد دولت می‌شود. به دنبال کاهش درآمدهای نفتی کشور در سال‌های اخیر یکی از مباحث نوین که در بین اقتصاددانان و سیاستمداران مطرح است وضع مالیات بر عایدات سهام و سود سپرده‌های بانکی می‌باشد. نظریه‌های متناقضی در مورد تاثیر وضع مالیات بر سود سپرده و نحوه اثرگذاری آن بر تولید وجود دارد. در مورد وضع مالیات بر عایدات سهام نیز نظرات متضادی در مورد تاثیری که مالیات بر سود سهام بر رفتار شرکت و در نتیجه بر عملکرد اقتصادی دارد وجود دارد. بر اساس دیدگاه جدید، مالیات از سود تقسیمی بر هزینه نهایی سرمایه تاثیر نمی‌گذارد و در نتیجه بر تصمیمات سرمایه‌گذاری تاثیری ندارد. بر اساس دیدگاه قدیمی، مالیات بر سود سهام تحریف‌کننده است و هزینه حقوق صاحبان سهام را افزایش می دهد. در این راستا هدف از مطالعه حاضر بررسی تاثیرات وضع مالیات بر عایدات سهام و سود سپرده بانکی بر متغیرهای کلان اقتصادی با رویکرد تعادل عمومی تصادفی پویا (dsge) طی سال‌های 1398-1370 می‌باشد. نتایج نشان‌گر آن است که با وضع مالیات بر عایدی سهام، میزان سرمایه‌گذاری مولد کاهش یافته و شرکت‌ها در تامین مالی با مشکل مواجه شده و میزان سرمایه آن‌ها کاهش می‌یابد و به دنبال آن تولید با کاهش روبرو ﻣﯽﮔﺮدد. با وضع مالیات بر سپرده‌های بانکی نیز نتایج مشابهی حاصل ﻣﯽﮔﺮدد به طوری که تولید از حالت با ثبات خود کاهش می‌یابد و دیدگاه قدیمی تایید ﻣﯽﮔﺮدد.

investigating the effects of stock earnings and bank deposits tax shocks in the context of keynesian dynamic stochastic general equilibrium

introduction: in most countries, government expenditures are provided from tax revenues. but, in iran, government budget depends on oil revenues. in other words, various economic activities in iran such as bank deposits interest and stock earnings are tax-exempt. although tax exemption pursues some goals, it reduces government revenues. in recent years, after severe sanctions against iran’s oil exports and a sharp drop in government oil revenues, increasing tax revenues has become one of the main alternatives to offset the decline in the oil revenues. on the other hand, the increased participation of investors in the stock market in recent years has provided a good opportunity for the government to increase its revenues in order to reduce budget deficits. dividends and interests on bank deposits can be considered as new tax bases. it is reported that the iranian national tax administration and the ministry of economic affairs and finance intend to levy taxes on bank deposits interests and dividends, but this plan has not yet been implemented. therefore, it is necessary to study this issue. in this regard, the purpose of this study is to investigate the effects of taxlng stock earnings and bank deposit interests on macroeconomic variables with a dynamic stochastic equilibrium (dsge) approach.methodology: this research investigated the effects of stock earnings and bank deposits tax shocks in the context of keynesian dynamic stochastic general equilibrium (dsge) approach during the years 1991-2019. the economic model in this study includes households, manufacturing enterprises, banks, government as fiscal policymakers and the central bank as monetary policymakers. intermediary firms operate in a monopoly competition framework, and the kalvo pricing method is used to express price rigidity. the purpose of using this method is to avoid model’s rapid adjustment in response to shocks. the problem with analyzing stochastic dynamic general equilibrium models is that equilibrium equations are nonlinear, so linearization is necessary. for linearization, taylor’s expansion method is applied. the linearized logarithm equations of household demand for stocks show that the amount of investment in the financial market depends on income, future price expectations and the expected dividends. to solve stochastic general equilibrium models, the parameters of the calibration model must be quantified. the conventional method to quantify the parameters is the calibration method. it is believed that the corresponding tax policy has not yet been implemented in iran. also, because of poor statistical data, this study uses the calibration method instead of bayesian method. in this method, the parameters of the model are selected in such a way that the best match is achieved between the predicted moments of the model and the real data moments of the iranian economy.results and discussion: the results show that taxation on bank deposit interests reduces the amount of bank reserves. then, as a result, banks request higher rate for lending, and the amount of loan demand is reduced. ultimately, the influx of cash into the production sector and investment decreases. the results of this model are consistent with gondolfi’s theory (1982) that states savings decrease due to increased interests on bank deposits. note that the government tax revenues increase with the imposition of a tax on bank deposits, but it soon deviates from its stable amount and then begins to decrease. this is due to the transfer of resources to other financial markets which are tax-exempt. furthermore, with the introduction of stock income tax, the demand for stock will decrease, so does the amount of productive investment. this makes companies face financing difficulties. with reduced level of total production, the disposable income of shareholders and consumption will be reduced.