condition mean min max ZT0-3 10.463699 10.463699 10.463699 ZT4-7 10.082896999999999 10.082896999999999 10.082896999999999 ZT8-11 9.4049295 9.4049295 9.4049295 ZT12-15 8.7612225 8.7612225 8.7612225 ZT16-19 9.574959 9.574959 9.574959 ZT20-23 13.4677655 13.4677655 13.4677655