As within the policies of left by companies each company provides different kinds of leave like casual leave, sick leave, earned leave, etc so you can also change the name of left as per the requirement and the policies of your company.
If yoneedof adding more employees then you can simply copy and paste the formula into the template. What you all have to do is every time you just need to update the year and month in your sheet and keep the rest of things the same as before. After every month you can easily create a new attendance form in which you can keep the record. You can also use this sheet to monitor the leave and attendance for a month of your employees.