condition mean min max ZT0-3 8.0339975 7.707155 8.36084 ZT4-7 13.414 13.414 13.414 ZT8-11 10.37978 10.37978 10.37978 ZT12-15 0 0 0 ZT16-19 10.368435 10.368435 10.368435 ZT20-23 10.37455 10.37455 10.37455