condition mean min max ZT0-3 39.680557 39.680557 39.680557 ZT4-7 39.7225465 39.7225465 39.7225465 ZT8-11 38.3267165 38.3267165 38.3267165 ZT12-15 33.8968025 33.8968025 33.8968025 ZT16-19 34.5332395 34.5332395 34.5332395 ZT20-23 40.164547 40.164547 40.164547