select High, Low, TRUNCATE((High + Low) / 2, 2) from `EOD-HD`;

2- select YEAR(Date), MONTH(Date), COUNT(id) from `EOD-HD` GROUP BY YEAR(Date), (MONTH(Date));

3 - SELECT MIN(`date`) AS `Range Start`, MAX(`date`) AS `Range End`, COUNT(*) AS `Count`
FROM `table`
GROUP BY FLOOR(PERIOD_DIFF(DATE_FORMAT('2013-01-01', '%Y%m'), DATE_FORMAT(`date`, '%Y%m')) / 3)
ORDER BY 1 DESC

4- SELECT Volume from `EOD-HD` ORDER BY Volume DESC LIMIT 10;