Online v/s pencil-paper

XAT - Xavier Aptitude Test - is an all India test conducted by XLRI (formerly known as Xavier Labour Relations Institute), a business school in Jamshedpur, as an entrance test for its management programmes as well as to many other reputed top B-schools in the country. Around 92,000 MBA aspirants gave the test this year on Jan 6, 2013.

XAT is a pencil-paper based test with three or four sections of multiple-choice questions. Each question paper consists of 25-30 sheets of paper. So, that makes it approximately 25 lakh sheets of paper printed every year. 

Hence, the question: Why hasn't XLRI shifted to the online test mode, especially when it could save roughly thirty 60-feet tall trees annually?