condition mean min max ZT0-3 950.105521 950.105521 950.105521 ZT4-7 547.555926 547.555926 547.555926 ZT8-11 628.8539355 628.8539355 628.8539355 ZT12-15 671.8403375 671.8403375 671.8403375 ZT16-19 1210.1776694999999 1210.1776694999999 1210.1776694999999 ZT20-23 1287.013557 1287.013557 1287.013557