MUMBAI: Researchers take an average of six years to complete their PhDs at IIT-Bombay, according to data from 1990 onwards, compiled by the institute's students. The maximum time to complete a PhD --- taken by two candidates -- was around 14 years and the fastest PhD was completed in two years. All four of these candidates were from the chemical engineering department. The data also shows that computer science engineers, on an average, take the longest time (6.7 years) to complete their PhDs as compared with candidates from other departments. Civil engineers take the least average time (5.1 years) to complete their PhDs. While the general perception on campus is that researchers take about five years, a majority of them, that is, around 32%, have taken six years on average. More than 40 candidates have taken 10 or more years to complete their PhDs. The two candidates from the chemical engineering department, who took about 14 years to finish their PhDs, are deemed by professors to be one-off cases. Of the other departments, PhD candidates from computer sciences and engineering, humanities, mathematics, bio-sciences and bioengineering and metallurgical engineering, have taken more than six years to complete their research . Civil engineering and earth sciences department candidates have taken the least time as compared with the others. Devang Khakhar, director of the institute, said that different departments have different range of time taken to complete Ph Ds. It also depends on the subject of research, he added. “The part-time Ph D candidates, which make up for a significant number, take longer than the others as the candidates are also doing jobs. The institute does not have a segregated list, but we will soon work on it and have a better analysis,” said Khakhar. Though the students have taken data available with the institute from 1990, not all PhDs before 1999, have uploaded their theses online, therefore the data before 1999 is incomplete. The analysis is based on data available online, said one student. “There’s a lot of data in the institute from various sources, and we thought it would be interesting if we present it in a visually intuitive way. There's tremendous scope for such analysis, and it'll throw interesting insights into various things,” said Mihir Kulkarni, one of the editors of Insight.