condition mean min max ZT0-3 251.794836 251.794836 251.794836 ZT4-7 265.715578 265.715578 265.715578 ZT8-11 236.41384999999997 236.41384999999997 236.41384999999997 ZT12-15 142.592476 142.592476 142.592476 ZT16-19 260.405818 260.405818 260.405818 ZT20-23 236.382408 236.382408 236.382408