Kolkata: While the average annual salary of graduates of the prestigious Indian Institutes of Technology (IITs) has dropped by five percent to 5.88 lakh, the salary of the National Institutes of Technology graduates has increased by six percent. According to the 5th IDC-Dataquest T-School 2009 Survey of 111 engineering colleges across the country, though the drop in the annual salary of IIT graduates has been ascribed to global recession, the average salary of NIT graduates has improved to 4.36 lakh. "Another reason for the drop in the annual salary of IIT graduates is that many bright students of IITs opted for higher studies instead of entering the job market," the survey pointed out. The highest annual salary received by an engineering graduate was from Netaji Subhas Institute of Technology (NSIT), New Delhi, who received 45 lakh from Schlumberger, the survey said. Due to the global slowdown, the average annual salary of engineering graduates countrywide stagnated at 3.5 lakh. But the average annual salary of engineering graduates in BPO/IT industry was a shade higher at 3.6 lakh.