Mark-Up Impact on Inflation in Iran's Economy

The purpose of this study is to investigate the determinants of inflation in the period 1960- 2011 and autoregressive model (VAR) is used here. In this study due to the structure of the Iranian economy, the mark-up index is derived and its growth growth along with liquidity growth, nominal exchange rate growth and productivity growth are used in the model. The results of Granger causality test show one-way causal relationship between the three variables of mark-up growth, exchange rates growth and labor productivity growth in one hand and inflation on the other hand, as well as two-way causal relationship between money growth and inflation. Also impuls response functions confirm a negative relationship between labor productivity growth and inflation. Moreover, based on the analysis of impulse response functions of three variables of mark-up growth, liquidity growth and exchange rate growth, they are positively correlated with inflation. Variance decomposition showed that each of the variables of inflation, mark-up growth and labor productivity growth in the short-term and respectively with the shares of 45, 29 and 25 percent, have the highest explanation on inflation forecast variance. But in the long run, the effect of mark-up growth is reduced, and labor productivity growth, inflation, liquidity growth, exchange rate growth and mark-up respectively explain 30, 28, 17, 14 and 10 percents of the forecast errors.