condition mean min max ZT0-3 10.207083 10.207083 10.207083 ZT4-7 10.627628 10.627628 10.627628 ZT8-11 11.984698 11.984698 11.984698 ZT12-15 13.104162 13.104162 13.104162 ZT16-19 26.4820645 26.4820645 26.4820645 ZT20-23 21.571213 21.571213 21.571213