Calculating student attendance using SQL

Question

Given the following table schemas, how would you figure out the overall attendance rate for each grade on 2018-03-12?

Table 1: student_attendance_log

column name	Data Type	Description
date	string	date of log per student_id, format is 'yyyy-mm-dd'
student_id	integer	id of the student
attendance_status	string	Possible values are ['present', 'tardy', 'absent']

Table 2: student_demographic

column name	Data Type	Description
student_id	integer	id of the student
grade_level	integer	will be a value between 0-12, which corresponds
date_of_birth	string	Student birth date, format is 'yyyy-mm-dd'

is my solution below correct?

select grade_level,
       sum(if(attendence_status = 'present', 1,0))/count(AD.student_id) as overall_attendance_rate
from student_demographic SD
  join student_attendance_log SL
    on SD.student_id = SL.student_id
   and date='2018-03-12'
group by 1