protected function get_data( $key, $data ) {

		$course = llms_get_post( $data );

		switch ( $key ) {

			case 'grade':
				$value = $course->get( 'average_grade' ) . '%';
				break;

			case 'id':
				$value = $this->get_post_link( $course->get( 'id' ) );
				break;

			case 'instructors':
				$data = array();
				foreach ( $course->get_instructors() as $info ) {
					$instructor = llms_get_instructor( $info['id'] );
					if ( $instructor ) {
						$data[] = sprintf( '%1$s (%2$s)', $instructor->get( 'display_name' ), $info['label'] );
					}
				}
				$value = implode( ', ', $data );
				break;

			case 'progress':
				$value = $this->get_progress_bar_html( $course->get( 'average_progress' ) );
				break;

			case 'students':
				$value = number_format_i18n( $course->get_student_count(), 0 );
				break;

			case 'title':
				$url   = LLMS_Admin_Reporting::get_current_tab_url(
					array(
						'tab'       => 'courses',
						'course_id' => $course->get( 'id' ),
					)
				);
				$value = '<a href="' . esc_url( $url ) . '">' . $course->get( 'title' ) . '</a>';
				break;

			default:
				$value = $key;

		}// End switch().

		return $value;
	}