condition mean min max ZT0-3 20.3272 20.3272 20.3272 ZT4-7 15.4464 15.4464 15.4464 ZT8-11 17.0138 17.0138 17.0138 ZT12-15 19.92105 19.92105 19.92105 ZT16-19 27.04925 27.04925 27.04925 ZT20-23 24.180999999999997 24.180999999999997 24.180999999999997