Indian inflation: don't blame it on support prices for foodgrains

Minimum support prices (MSP) for foodgrains have been rising over the years (although the new government has kept increases under control). This is said to be a driver of inflation in recent years.

Amartya Lahiri, writing in IE, thinks the explanation facile. Why? Because MSP increases themselves result from a rise in past inflation! 

In as much as the MSP itself responds to current and past inflation, a part of the reported effect of the MSP on inflation is then just the effect of past inflation on current inflation, rather than any independent effect of changes in the MSP on inflation. The MSP may well have an independent effect on inflation, but to determine that one needs to break up MSP inflation into two parts: the part that is induced by current and past inflation and the part that is not. The key test then is to see which of these two components of the MSP has the bigger effect on inflation.

Using the CPI (industrial workers) and a weighted MSP index for the period of 1976-2014, I did precisely that exercise. The bottom-line of the results is that, using the part of the MSP due to past inflation to predict inflation does almost as good a job
as using the overall MSP. Moreover, when both components of MSP changes are used to predict inflation, the effect of inflation-induced MSP is three times as high as that of non-inflation MSP. The main implication of this is that the biggest predictor of inflation is past inflation. It is clear that past MSP changes due to inflation account for a much larger part of overall CPI inflation than does non-inflation MSP.
- See more at: http://indianexpress.com/article/opinion/columns/dont-blame-msp-for-inflation/#sthash.HZexjpVx.dpuf

Using the CPI (industrial workers) and a weighted MSP index for the period of 1976-2014, I did precisely that exercise. The bottom-line of the results is that, using the part of the MSP due to past inflation to predict inflation does almost as good a job as using the overall MSP. Moreover, when both components of MSP changes are used to predict inflation, the effect of inflation-induced MSP is three times as high as that of non-inflation MSP. The main implication of this is that the biggest predictor of inflation is past inflation. It is clear that past MSP changes due to inflation account for a much larger part of overall CPI inflation than does non-inflation MSP.

In as much as the MSP itself responds to current and past inflation, a part of the reported effect of the MSP on inflation is then just the effect of past inflation on current inflation, rather than any independent effect of changes in the MSP on inflation. The MSP may well have an independent effect on inflation, but to determine that one needs to break up MSP inflation into two parts: the part that is induced by current and past inflation and the part that is not. The key test then is to see which of these two components of the MSP has the bigger effect on inflation. - See more at: http://indianexpress.com/article/opinion/columns/dont-blame-msp-for-inflation/#sthash.HZexjpVx.dpuf

In as much as the MSP itself responds to current and past inflation, a part of the reported effect of the MSP on inflation is then just the effect of past inflation on current inflation, rather than any independent effect of changes in the MSP on inflation. The MSP may well have an independent effect on inflation, but to determine that one needs to break up MSP inflation into two parts: the part that is induced by current and past inflation and the part that is not. The key test then is to see which of these two components of the MSP has the bigger effect on inflation. - See more at: http://indianexpress.com/article/opinion/columns/dont-blame-msp-for-inflation/#sthash.HZexjpVx.dpuf

In as much as the MSP itself responds to current and past inflation, a part of the reported effect of the MSP on inflation is then just the effect of past inflation on current inflation, rather than any independent effect of changes in the MSP on inflation. The MSP may well have an independent effect on inflation, but to determine that one needs to break up MSP inflation into two parts: the part that is induced by current and past inflation and the part that is not. The key test then is to see which of these two components of the MSP has the bigger effect on inflation. - See more at: http://indianexpress.com/article/opinion/columns/dont-blame-msp-for-inflation/#sthash.HZexjpVx.dpuf

In as much as the MSP itself responds to current and past inflation, a part of the reported effect of the MSP on inflation is then just the effect of past inflation on current inflation, rather than any independent effect of changes in the MSP on inflation. The MSP may well have an independent effect on inflation, but to determine that one needs to break up MSP inflation into two parts: the part that is induced by current and past inflation and the part that is not. The key test then is to see which of these two components of the MSP has the bigger effect on inflation. - See more at: http://indianexpress.com/article/opinion/columns/dont-blame-msp-for-inflation/#sthash.HZexjpVx.dpuf

In as much as the MSP itself responds to current and past inflation, a part of the reported effect of the MSP on inflation is then just the effect of past inflation on current inflation, rather than any independent effect of changes in the MSP on inflation. The MSP may well have an independent effect on inflation, but to determine that one needs to break up MSP inflation into two parts: the part that is induced by current and past inflation and the part that is not. The key test then is to see which of these two components of the MSP has the bigger effect on inflation. - See more at: http://indianexpress.com/article/opinion/columns/dont-blame-msp-for-inflation/#sthash.HZexjpVx.dpuf