condition mean min max ZT0-3 15.79355 15.79355 15.79355 ZT4-7 14.6619 14.6619 14.6619 ZT8-11 14.7481 14.7481 14.7481 ZT12-15 11.4466 11.4466 11.4466 ZT16-19 14.45665 14.45665 14.45665 ZT20-23 14.908249999999999 14.908249999999999 14.908249999999999