How long did the traditional method of voting, with stamped ballot papers, continue in India?

40 years

After the initial phase, a new method was introduced. The ballot paper now featured the names and symbols of all candidates, and voters were required to put a stamp on the name of their chosen candidate. This method remained in practice for approximately forty years. Towards the late 1990s, the Election Commission introduced Electronic Voting Machines (EVMs). By 2004, the entire country had transitioned to using EVMs for elections.