condition mean min max ZT0-3 902.267582 902.267582 902.267582 ZT4-7 333.50762000000003 333.50762000000003 333.50762000000003 ZT8-11 358.1509365 358.1509365 358.1509365 ZT12-15 422.0588555 422.0588555 422.0588555 ZT16-19 313.8607915 313.8607915 313.8607915 ZT20-23 276.3286315 276.3286315 276.3286315