condition mean min max ZT0-3 30.198104 30.198104 30.198104 ZT4-7 22.393494 22.393494 22.393494 ZT8-11 35.746616 35.746616 35.746616 ZT12-15 155.5595075 155.5595075 155.5595075 ZT16-19 136.752541 136.752541 136.752541 ZT20-23 290.164303 290.164303 290.164303