function reportNewSpeakersPerCon()
{
$conn = getDb();
$sql = "SELECT event.start_date, event.name, talks_count, num_speakers, new_speakers, FORMAT((new_speakers/event.num_speakers)*100, 1) AS percent_new\n FROM event\n WHERE start_date >= '2010-01-01'\n ORDER BY start_date";
$stmt = $conn->executeQuery($sql);
$rows = $stmt->fetchAll();
$header = ['Date', 'Event', 'Total sessions', 'Speakers', 'New speakers', 'Percent new'];
$stmt = $conn->executeQuery("SELECT 'N/A', 'Average', FORMAT(AVG(talks_count), 1), FORMAT(AVG(num_speakers), 1), FORMAT(AVG(new_speakers), 1), FORMAT(AVG(percent_new), 1) FROM ({$sql}) AS stuff");
$averages = $stmt->fetch();
return makeHtmlTable('First time speakers', $header, $rows, $averages);
}
public function __toString()
{
return makeHtmlTable($this->caption, $this->header, $this->rows, $this->footer);
}
