condition mean min max ZT0-3 3.0826124999999998 2.501575 3.66365 ZT4-7 1.879495 1.879495 1.879495 ZT8-11 1.88491 1.88491 1.88491 ZT12-15 0 0 0 ZT16-19 2.7576650000000003 2.7576650000000003 2.7576650000000003 ZT20-23 2.56215 2.56215 2.56215