• Dr. Y. Raghunatha Reddy
• Dr. S.V. Suneetha
• Dr. N. Sreedhar
• Dr. G. Rama Krishna

The Goods and Services Tax (GST) in India, introduced in 2017, has undergone multiple rate revisions between 2018 and 2024, potentially influencing consumer prices across sectors. This study investigates the causal impact of GST rate changes on the Consumer Price Index (CPI) in India using monthly CPI data published by the Ministry of Statistics and Programme Implementation (MOSPI) alongside GST Council notifications. Employing Interrupted Time Series (ITS) and Difference-in-Differences (DiD) methodologies, the analysis isolates the effect of GST adjustments on CPI trends while controlling for macroeconomic factors such as fuel prices and interest rates. Bootstrap resampling is applied to obtain robust confidence intervals for treatment effects, and results are compared against classical parametric estimates. Preliminary findings suggest that CPI categories directly linked to GST rate revisions, particularly in non-food goods and services, exhibit statistically significant shifts in trend and level post-policy change, whereas categories less affected by GST remain stable. The study contributes to policy evaluation literature by quantifying GST’s inflationary effects and demonstrating the advantages of causal inference techniques over traditional trend analysis in macroeconomic policy assessment.

Key Words: GST, ITS in GST, DiD in GST, Bootstrap method, etc.

"CAUSAL IMPACT OF GST RATE CHANGES ON CONSUMER PRICE INDEX IN INDIA (2018–2024): A STATISTICAL INFERENCE APPROACH", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.12, Issue 9, page no.e633-e638, September-2025, Available :http://www.jetir.org/papers/JETIR2509472.pdf

"CAUSAL IMPACT OF GST RATE CHANGES ON CONSUMER PRICE INDEX IN INDIA (2018–2024): A STATISTICAL INFERENCE APPROACH", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.12, Issue 9, page no. ppe633-e638, September-2025, Available at : http://www.jetir.org/papers/JETIR2509472.pdf