Does the pattern of wholesale price index of India changes every year in the last ten years – what curves tells us

Abstract

This paper aims to analyze the year wise pattern of the Wholesale Price Index of India for the last 10 (ten) years and have employed the curve fitting techniques for doing the analysis. We have taken the Wholesale Price Index of all the Commodities of India as dependent variable and Time as independent variable and have found the best fit curve for every year staring from 2004 to 2014. Three different families of fits have been employed for this study namely Polynomial, Exponential and Gaussian. It has been observed that in the first 6 (six) years i.e. from 2005 to 2010, Polynomial type of fit is found to be the best fit for 2005 (Cubic), 2008 (Cubic) and 2010 (Linear); Exponential type of fit is best fit for 2009 (Exponential1) and Gaussian type of fit is best for the years 2006 and 2007 (both Gaussian2). In the last 4 (four) years i.e. from 2011 to 2014, Gaussian type of fit is found to be the best fit (2011 – Gaussian1 and 2012, 2013 & 2014 – all Gaussian2) and thereby exhibiting a particular pattern for the last 4 (four) years under study.