public function set_columns() {
		return array(
			'id'                    => array(
				'exportable' => true,
				'sortable'   => true,
				'title'      => __( 'ID', 'lifterlms' ),
			),
			'email'                 => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Email', 'lifterlms' ),
			),
			'name'                  => array(
				'sortable' => true,
				'title'    => __( 'Name', 'lifterlms' ),
			),
			'name_last'             => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Last Name', 'lifterlms' ),
			),
			'name_first'            => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'First Name', 'lifterlms' ),
			),
			'registered'            => array(
				'exportable' => true,
				'sortable'   => true,
				'title'      => __( 'Registration Date', 'lifterlms' ),
			),
			'last_seen'             => array(
				'exportable' => true,
				'sortable'   => false,
				'title'      => __( 'Last Seen', 'lifterlms' ),
			),
			'overall_progress'      => array(
				'exportable' => true,
				'sortable'   => true,
				'title'      => __( 'Progress', 'lifterlms' ),
			),
			'overall_grade'         => array(
				'exportable' => true,
				'sortable'   => true,
				'title'      => __( 'Grade', 'lifterlms' ),
			),
			'enrollments'           => array(
				'sortable' => false,
				'title'    => __( 'Enrollments', 'lifterlms' ),
			),
			'completions'           => array(
				'sortable' => false,
				'title'    => __( 'Completions', 'lifterlms' ),
			),
			'certificates'          => array(
				'sortable' => false,
				'title'    => __( 'Certificates', 'lifterlms' ),
			),
			'achievements'          => array(
				'sortable' => false,
				'title'    => __( 'Achievements', 'lifterlms' ),
			),
			'memberships'           => array(
				'sortable' => false,
				'title'    => __( 'Memberships', 'lifterlms' ),
			),
			'billing_address_1'     => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Billing Address 1', 'lifterlms' ),
			),
			'billing_address_2'     => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Billing Address 2', 'lifterlms' ),
			),
			'billing_city'          => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Billing City', 'lifterlms' ),
			),
			'billing_state'         => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Billing State', 'lifterlms' ),
			),
			'billing_zip'           => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Billing Zip', 'lifterlms' ),
			),
			'billing_country'       => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Billing Country', 'lifterlms' ),
			),
			'phone'                 => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Phone', 'lifterlms' ),
			),
			'courses_enrolled'      => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Courses (Enrolled)', 'lifterlms' ),
			),
			'courses_cancelled'     => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Courses (Cancelled)', 'lifterlms' ),
			),
			'courses_expired'       => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Courses (Expired)', 'lifterlms' ),
			),
			'memberships_enrolled'  => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Memberships (Enrolled)', 'lifterlms' ),
			),
			'memberships_cancelled' => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Memberships (Cancelled)', 'lifterlms' ),
			),
			'memberships_expired'   => array(
				'exportable'  => true,
				'export_only' => true,
				'title'       => __( 'Memberships (Expired)', 'lifterlms' ),
			),
		);
	}