condition mean min max ZT0-3 9.519393 9.519393 9.519393 ZT4-7 9.7592775 9.7592775 9.7592775 ZT8-11 9.711776 9.711776 9.711776 ZT12-15 9.331177499999999 9.331177499999999 9.331177499999999 ZT16-19 8.5424955 8.5424955 8.5424955 ZT20-23 9.976236499999999 9.976236499999999 9.976236499999999