Value Added Tax (VAT) was introduced in India to replace State Sales Tax. Most states implemented VAT from April 1, 2005. Among the states listed, Andhra Pradesh, Chhattisgarh, and Maharashtra were part of the first phase of VAT implementation starting April 1, 2005. Uttar Pradesh was one of the last major states to implement VAT, doing so much later (January 1, 2008). Therefore, Uttar Pradesh (4) had not introduced VAT system around the time the question is likely framed (mid-2000s). Andhra Pradesh (1) had introduced it.