condition mean min max ZT0-3 13.615643 13.615643 13.615643 ZT4-7 11.2124665 11.2124665 11.2124665 ZT8-11 10.947752000000001 10.947752000000001 10.947752000000001 ZT12-15 11.4478995 11.4478995 11.4478995 ZT16-19 12.092278499999999 12.092278499999999 12.092278499999999 ZT20-23 10.0590945 10.0590945 10.0590945