condition mean min max ZT0-3 10.042335 7.88392 12.20075 ZT4-7 4.24367 4.24367 4.24367 ZT8-11 4.08128 4.08128 4.08128 ZT12-15 0 0 0 ZT16-19 4.306475 4.306475 4.306475 ZT20-23 5.914045 5.914045 5.914045