condition mean min max ZT0-3 259.083639 259.083639 259.083639 ZT4-7 478.9431485 478.9431485 478.9431485 ZT8-11 540.633872 540.633872 540.633872 ZT12-15 647.8038650000001 647.8038650000001 647.8038650000001 ZT16-19 435.46353150000004 435.46353150000004 435.46353150000004 ZT20-23 216.371691 216.371691 216.371691