Laravel 7: Automatically add values to a column on first day of every month

I want to add value to specific column for all rows in a table every month.

Users Table:

Controller:

public function earned_leave(){
  $user = User::where('leave_alloc', '!=', null)->get();
  foreach($user as $row){
    $leave_alloc = $row->leave_alloc;
    $earned_leave = $leave_alloc / 12;
    $row->leave_earn += $earned_leave;
    $row->save();
  }
}

Here $earned_leave will be the result of $leave_alloc divided by 12. So, on the first day of every month, I want to add the earned leave amount to the leave_earn column of all users. This column can hold a negative value and decimal value.

How can I make this automation?

Laravel support task scheduling. For your task you may use ->monthlyOn(4, '15:00');

In most simple realization it looks like

$schedule->call(function () {
  $user = User::where('leave_alloc', '!=', null)->get();
  foreach($user as $row){
    $earned_leave = $row->leave_alloc / 12;
    $row->leave_earn += $earned_leave;
    $row->save();
  }
})->monthlyOn(1, '12:00');

Don't forget to add Cron entry