condition mean min max ZT0-3 6.885625 5.446405 7.732175 ZT4-7 6.137875 6.137875 6.137875 ZT8-11 7.209595 7.209595 7.209595 ZT12-15 9.3997475 8.651775 10.14772 ZT16-19 10.105599999999999 10.105599999999999 10.105599999999999 ZT20-23 11.5577 11.5577 11.5577