condition mean min max ZT0-3 15.682787 15.682787 15.682787 ZT4-7 17.608951 17.608951 17.608951 ZT8-11 18.3536425 18.3536425 18.3536425 ZT12-15 16.146712 16.146712 16.146712 ZT16-19 15.4457275 15.4457275 15.4457275 ZT20-23 16.535265000000003 16.535265000000003 16.535265000000003