condition mean min max ZT0-3 18.15445 18.15445 18.15445 ZT4-7 25.9602315 25.9602315 25.9602315 ZT8-11 18.818129 18.818129 18.818129 ZT12-15 15.8736705 15.8736705 15.8736705 ZT16-19 16.251927 16.251927 16.251927 ZT20-23 15.3168045 15.3168045 15.3168045