Dear Mr Anil Babu
Thanks for your quick response.
For example, Student# 1004 came to exam hall at 12.15pm so the system should count 1 in the time table 11.30 - 12.30. The correct answer should be 165 (see Attendance Report By Date).
The problem is why Attendance Report By Hour and Charts (Table 1 & Table 2) showed different results.