condition mean min max ZT0-3 1321.737712 1321.737712 1321.737712 ZT4-7 1481.986344 1481.986344 1481.986344 ZT8-11 1543.9540285 1543.9540285 1543.9540285 ZT12-15 1668.791458 1668.791458 1668.791458 ZT16-19 2099.3461615 2099.3461615 2099.3461615 ZT20-23 1761.281973 1761.281973 1761.281973