condition mean min max ZT0-3 2.3245523085 2.301276658 2.347827959 ZT4-7 4.15259702375 3.023876624 5.2813174235 ZT8-11 5.766836014500001 5.7139283035 5.8197437255 ZT12-15 3.9022088562499997 3.092710646 4.7117070665 ZT16-19 3.50080687975 2.93143714 4.0701766195 ZT20-23 5.5518010855 5.160696071 5.9429061