condition mean min max ZT0-3 13.345125000000001 7.822975 16.9491 ZT4-7 6.479825 6.479825 6.479825 ZT8-11 7.54399 7.54399 7.54399 ZT12-15 10.9079875 8.900825000000001 12.91515 ZT16-19 13.97705 13.97705 13.97705 ZT20-23 17.60745 17.60745 17.60745