condition mean min max ZT0-3 5.24662751 2.841415975 7.651839045 ZT4-7 4.9434212232500006 3.219861397 6.6669810495 ZT8-11 7.75458361025 6.5885451565 8.920622064 ZT12-15 6.5233138565 6.307947188 6.738680525 ZT16-19 4.99937174375 4.576884262 5.4218592255 ZT20-23 7.10357926625 6.333778242 7.8733802905